17 #define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18 #define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19 #define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20 #define SSH1_CMSG_USER 4 /* 0x4 */
21 #define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22 #define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23 #define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24 #define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25 #define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26 #define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27 #define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28 #define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29 #define SSH1_SMSG_SUCCESS 14 /* 0xe */
30 #define SSH1_SMSG_FAILURE 15 /* 0xf */
31 #define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32 #define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33 #define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34 #define SSH1_CMSG_EOF 19 /* 0x13 */
35 #define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36 #define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37 #define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38 #define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39 #define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40 #define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41 #define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42 #define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43 #define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44 #define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45 #define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46 #define SSH1_MSG_IGNORE 32 /* 0x20 */
47 #define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48 #define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49 #define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50 #define SSH1_MSG_DEBUG 36 /* 0x24 */
51 #define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52 #define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53 #define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54 #define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55 #define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56 #define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57 #define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
59 #define SSH1_AUTH_TIS 5 /* 0x5 */
60 #define SSH1_AUTH_CCARD 16 /* 0x10 */
62 #define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
63 /* Mask for protoflags we will echo back to server if seen */
64 #define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
66 #define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67 #define SSH2_MSG_IGNORE 2 /* 0x2 */
68 #define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69 #define SSH2_MSG_DEBUG 4 /* 0x4 */
70 #define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71 #define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72 #define SSH2_MSG_KEXINIT 20 /* 0x14 */
73 #define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74 #define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75 #define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76 #define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77 #define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78 #define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79 #define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80 #define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81 #define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82 #define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83 #define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84 #define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85 #define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
86 #define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87 #define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
88 #define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89 #define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90 #define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91 #define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92 #define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93 #define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94 #define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95 #define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96 #define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97 #define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98 #define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99 #define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100 #define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101 #define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
107 #define SSH2_PKTCTX_DHGROUP1 0x0001
108 #define SSH2_PKTCTX_DHGEX 0x0002
109 #define SSH2_PKTCTX_PUBLICKEY 0x0010
110 #define SSH2_PKTCTX_PASSWORD 0x0020
111 #define SSH2_PKTCTX_KBDINTER 0x0040
112 #define SSH2_PKTCTX_AUTH_MASK 0x00F0
114 #define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
115 #define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
116 #define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
117 #define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
118 #define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
119 #define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
120 #define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
121 #define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
122 #define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
123 #define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
124 #define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
125 #define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
126 #define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
127 #define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
128 #define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
130 static const char *const ssh2_disconnect_reasons
[] = {
132 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
133 "SSH_DISCONNECT_PROTOCOL_ERROR",
134 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
135 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
136 "SSH_DISCONNECT_MAC_ERROR",
137 "SSH_DISCONNECT_COMPRESSION_ERROR",
138 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
139 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
140 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
141 "SSH_DISCONNECT_CONNECTION_LOST",
142 "SSH_DISCONNECT_BY_APPLICATION",
143 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
144 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
145 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
146 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
149 #define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
150 #define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
151 #define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
152 #define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
154 #define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
157 * Various remote-bug flags.
159 #define BUG_CHOKES_ON_SSH1_IGNORE 1
160 #define BUG_SSH2_HMAC 2
161 #define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
162 #define BUG_CHOKES_ON_RSA 8
163 #define BUG_SSH2_RSA_PADDING 16
164 #define BUG_SSH2_DERIVEKEY 32
165 #define BUG_SSH2_DH_GEX 64
166 #define BUG_SSH2_PK_SESSIONID 128
168 #define translate(x) if (type == x) return #x
169 #define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
170 static char *ssh1_pkt_type(int type
)
172 translate(SSH1_MSG_DISCONNECT
);
173 translate(SSH1_SMSG_PUBLIC_KEY
);
174 translate(SSH1_CMSG_SESSION_KEY
);
175 translate(SSH1_CMSG_USER
);
176 translate(SSH1_CMSG_AUTH_RSA
);
177 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE
);
178 translate(SSH1_CMSG_AUTH_RSA_RESPONSE
);
179 translate(SSH1_CMSG_AUTH_PASSWORD
);
180 translate(SSH1_CMSG_REQUEST_PTY
);
181 translate(SSH1_CMSG_WINDOW_SIZE
);
182 translate(SSH1_CMSG_EXEC_SHELL
);
183 translate(SSH1_CMSG_EXEC_CMD
);
184 translate(SSH1_SMSG_SUCCESS
);
185 translate(SSH1_SMSG_FAILURE
);
186 translate(SSH1_CMSG_STDIN_DATA
);
187 translate(SSH1_SMSG_STDOUT_DATA
);
188 translate(SSH1_SMSG_STDERR_DATA
);
189 translate(SSH1_CMSG_EOF
);
190 translate(SSH1_SMSG_EXIT_STATUS
);
191 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
);
192 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE
);
193 translate(SSH1_MSG_CHANNEL_DATA
);
194 translate(SSH1_MSG_CHANNEL_CLOSE
);
195 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
);
196 translate(SSH1_SMSG_X11_OPEN
);
197 translate(SSH1_CMSG_PORT_FORWARD_REQUEST
);
198 translate(SSH1_MSG_PORT_OPEN
);
199 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING
);
200 translate(SSH1_SMSG_AGENT_OPEN
);
201 translate(SSH1_MSG_IGNORE
);
202 translate(SSH1_CMSG_EXIT_CONFIRMATION
);
203 translate(SSH1_CMSG_X11_REQUEST_FORWARDING
);
204 translate(SSH1_CMSG_AUTH_RHOSTS_RSA
);
205 translate(SSH1_MSG_DEBUG
);
206 translate(SSH1_CMSG_REQUEST_COMPRESSION
);
207 translate(SSH1_CMSG_AUTH_TIS
);
208 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE
);
209 translate(SSH1_CMSG_AUTH_TIS_RESPONSE
);
210 translate(SSH1_CMSG_AUTH_CCARD
);
211 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE
);
212 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE
);
215 static char *ssh2_pkt_type(int pkt_ctx
, int type
)
217 translate(SSH2_MSG_DISCONNECT
);
218 translate(SSH2_MSG_IGNORE
);
219 translate(SSH2_MSG_UNIMPLEMENTED
);
220 translate(SSH2_MSG_DEBUG
);
221 translate(SSH2_MSG_SERVICE_REQUEST
);
222 translate(SSH2_MSG_SERVICE_ACCEPT
);
223 translate(SSH2_MSG_KEXINIT
);
224 translate(SSH2_MSG_NEWKEYS
);
225 translatec(SSH2_MSG_KEXDH_INIT
, SSH2_PKTCTX_DHGROUP1
);
226 translatec(SSH2_MSG_KEXDH_REPLY
, SSH2_PKTCTX_DHGROUP1
);
227 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST
, SSH2_PKTCTX_DHGEX
);
228 translatec(SSH2_MSG_KEX_DH_GEX_GROUP
, SSH2_PKTCTX_DHGEX
);
229 translatec(SSH2_MSG_KEX_DH_GEX_INIT
, SSH2_PKTCTX_DHGEX
);
230 translatec(SSH2_MSG_KEX_DH_GEX_REPLY
, SSH2_PKTCTX_DHGEX
);
231 translate(SSH2_MSG_USERAUTH_REQUEST
);
232 translate(SSH2_MSG_USERAUTH_FAILURE
);
233 translate(SSH2_MSG_USERAUTH_SUCCESS
);
234 translate(SSH2_MSG_USERAUTH_BANNER
);
235 translatec(SSH2_MSG_USERAUTH_PK_OK
, SSH2_PKTCTX_PUBLICKEY
);
236 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ
, SSH2_PKTCTX_PASSWORD
);
237 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST
, SSH2_PKTCTX_KBDINTER
);
238 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE
, SSH2_PKTCTX_KBDINTER
);
239 translate(SSH2_MSG_GLOBAL_REQUEST
);
240 translate(SSH2_MSG_REQUEST_SUCCESS
);
241 translate(SSH2_MSG_REQUEST_FAILURE
);
242 translate(SSH2_MSG_CHANNEL_OPEN
);
243 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
244 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
245 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
246 translate(SSH2_MSG_CHANNEL_DATA
);
247 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
248 translate(SSH2_MSG_CHANNEL_EOF
);
249 translate(SSH2_MSG_CHANNEL_CLOSE
);
250 translate(SSH2_MSG_CHANNEL_REQUEST
);
251 translate(SSH2_MSG_CHANNEL_SUCCESS
);
252 translate(SSH2_MSG_CHANNEL_FAILURE
);
258 #define GET_32BIT(cp) \
259 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
260 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
261 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
262 ((unsigned long)(unsigned char)(cp)[3]))
264 #define PUT_32BIT(cp, value) { \
265 (cp)[0] = (unsigned char)((value) >> 24); \
266 (cp)[1] = (unsigned char)((value) >> 16); \
267 (cp)[2] = (unsigned char)((value) >> 8); \
268 (cp)[3] = (unsigned char)(value); }
270 enum { PKT_END
, PKT_INT
, PKT_CHAR
, PKT_DATA
, PKT_STR
, PKT_BIGNUM
};
273 * Coroutine mechanics for the sillier bits of the code. If these
274 * macros look impenetrable to you, you might find it helpful to
277 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
279 * which explains the theory behind these macros.
281 #define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
284 if (!ssh->t) ssh->t = smalloc(sizeof(struct t)); \
286 #define crFinish(z) } *crLine = 0; return (z); }
287 #define crFinishV } *crLine = 0; return; }
288 #define crReturn(z) \
290 *crLine =__LINE__; return (z); case __LINE__:;\
294 *crLine=__LINE__; return; case __LINE__:;\
296 #define crStop(z) do{ *crLine = 0; return (z); }while(0)
297 #define crStopV do{ *crLine = 0; return; }while(0)
298 #define crWaitUntil(c) do { crReturn(0); } while (!(c))
299 #define crWaitUntilV(c) do { crReturnV; } while (!(c))
301 typedef struct ssh_tag
*Ssh
;
303 static void ssh2_pkt_init(Ssh
, int pkt_type
);
304 static void ssh2_pkt_addbool(Ssh
, unsigned char value
);
305 static void ssh2_pkt_adduint32(Ssh
, unsigned long value
);
306 static void ssh2_pkt_addstring_start(Ssh
);
307 static void ssh2_pkt_addstring_str(Ssh
, char *data
);
308 static void ssh2_pkt_addstring_data(Ssh
, char *data
, int len
);
309 static void ssh2_pkt_addstring(Ssh
, char *data
);
310 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
);
311 static void ssh2_pkt_addmp(Ssh
, Bignum b
);
312 static int ssh2_pkt_construct(Ssh
);
313 static void ssh2_pkt_send(Ssh
);
316 * Buffer management constants. There are several of these for
317 * various different purposes:
319 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
320 * on a local data stream before we throttle the whole SSH
321 * connection (in SSH1 only). Throttling the whole connection is
322 * pretty drastic so we set this high in the hope it won't
325 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
326 * on the SSH connection itself before we defensively throttle
327 * _all_ local data streams. This is pretty drastic too (though
328 * thankfully unlikely in SSH2 since the window mechanism should
329 * ensure that the server never has any need to throttle its end
330 * of the connection), so we set this high as well.
332 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
336 #define SSH1_BUFFER_LIMIT 32768
337 #define SSH_MAX_BACKLOG 32768
338 #define OUR_V2_WINSIZE 16384
340 const static struct ssh_kex
*kex_algs
[] = {
341 &ssh_diffiehellman_gex
,
345 const static struct ssh_signkey
*hostkey_algs
[] = { &ssh_rsa
, &ssh_dss
};
347 static void *nullmac_make_context(void)
351 static void nullmac_free_context(void *handle
)
354 static void nullmac_key(void *handle
, unsigned char *key
)
357 static void nullmac_generate(void *handle
, unsigned char *blk
, int len
,
361 static int nullmac_verify(void *handle
, unsigned char *blk
, int len
,
366 const static struct ssh_mac ssh_mac_none
= {
367 nullmac_make_context
, nullmac_free_context
, nullmac_key
,
368 nullmac_generate
, nullmac_verify
, "none", 0
370 const static struct ssh_mac
*macs
[] = {
371 &ssh_sha1
, &ssh_md5
, &ssh_mac_none
373 const static struct ssh_mac
*buggymacs
[] = {
374 &ssh_sha1_buggy
, &ssh_md5
, &ssh_mac_none
377 static void *ssh_comp_none_init(void)
381 static void ssh_comp_none_cleanup(void *handle
)
384 static int ssh_comp_none_block(void *handle
, unsigned char *block
, int len
,
385 unsigned char **outblock
, int *outlen
)
389 static int ssh_comp_none_disable(void *handle
)
393 const static struct ssh_compress ssh_comp_none
= {
395 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
396 ssh_comp_none_init
, ssh_comp_none_cleanup
, ssh_comp_none_block
,
397 ssh_comp_none_disable
, NULL
399 extern const struct ssh_compress ssh_zlib
;
400 const static struct ssh_compress
*compressions
[] = {
401 &ssh_zlib
, &ssh_comp_none
404 enum { /* channel types */
409 CHAN_SOCKDATA_DORMANT
/* one the remote hasn't confirmed */
413 * 2-3-4 tree storing channels.
416 Ssh ssh
; /* pointer back to main context */
417 unsigned remoteid
, localid
;
420 * In SSH1, this value contains four bits:
422 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
423 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
424 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
425 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
427 * A channel is completely finished with when all four bits are set.
431 struct ssh1_data_channel
{
434 struct ssh2_data_channel
{
436 unsigned remwindow
, remmaxpkt
;
441 struct ssh_agent_channel
{
442 unsigned char *message
;
443 unsigned char msglen
[4];
444 int lensofar
, totallen
;
446 struct ssh_x11_channel
{
449 struct ssh_pfd_channel
{
456 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
457 * 2 use this structure in different ways, reflecting SSH 2's
458 * altogether saner approach to port forwarding.
460 * In SSH 1, you arrange a remote forwarding by sending the server
461 * the remote port number, and the local destination host:port.
462 * When a connection comes in, the server sends you back that
463 * host:port pair, and you connect to it. This is a ready-made
464 * security hole if you're not on the ball: a malicious server
465 * could send you back _any_ host:port pair, so if you trustingly
466 * connect to the address it gives you then you've just opened the
467 * entire inside of your corporate network just by connecting
468 * through it to a dodgy SSH server. Hence, we must store a list of
469 * host:port pairs we _are_ trying to forward to, and reject a
470 * connection request from the server if it's not in the list.
472 * In SSH 2, each side of the connection minds its own business and
473 * doesn't send unnecessary information to the other. You arrange a
474 * remote forwarding by sending the server just the remote port
475 * number. When a connection comes in, the server tells you which
476 * of its ports was connected to; and _you_ have to remember what
477 * local host:port pair went with that port number.
479 * Hence: in SSH 1 this structure stores host:port pairs we intend
480 * to allow connections to, and is indexed by those host:port
481 * pairs. In SSH 2 it stores a mapping from source port to
482 * destination host:port pair, and is indexed by source port.
484 struct ssh_rportfwd
{
485 unsigned sport
, dport
;
498 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
499 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
500 static void ssh_size(void *handle
, int width
, int height
);
501 static void ssh_special(void *handle
, Telnet_Special
);
502 static int ssh2_try_send(struct ssh_channel
*c
);
503 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
, int len
);
504 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
);
505 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
);
506 static int ssh_sendbuffer(void *handle
);
508 struct rdpkt1_state_tag
{
509 long len
, pad
, biglen
, to_read
;
510 unsigned long realcrc
, gotcrc
;
516 struct rdpkt2_state_tag
{
517 long len
, pad
, payload
, packetlen
, maclen
;
520 unsigned long incoming_sequence
;
524 const struct plug_function_table
*fn
;
525 /* the above field _must_ be first in the structure */
527 SHA_State exhash
, exhashbase
;
534 unsigned char session_key
[32];
536 int v1_remote_protoflags
;
537 int v1_local_protoflags
;
538 int agentfwd_enabled
;
541 const struct ssh_cipher
*cipher
;
544 const struct ssh2_cipher
*cscipher
, *sccipher
;
545 void *cs_cipher_ctx
, *sc_cipher_ctx
;
546 const struct ssh_mac
*csmac
, *scmac
;
547 void *cs_mac_ctx
, *sc_mac_ctx
;
548 const struct ssh_compress
*cscomp
, *sccomp
;
549 void *cs_comp_ctx
, *sc_comp_ctx
;
550 const struct ssh_kex
*kex
;
551 const struct ssh_signkey
*hostkey
;
552 unsigned char v2_session_id
[20];
558 int echoing
, editing
;
562 int term_width
, term_height
;
564 tree234
*channels
; /* indexed by local id */
565 struct ssh_channel
*mainchan
; /* primary session channel */
572 SSH_STATE_BEFORE_SIZE
,
578 int size_needed
, eof_needed
;
581 struct Packet pktout
;
582 unsigned char *deferred_send_data
;
583 int deferred_len
, deferred_size
;
586 * Gross hack: pscp will try to start SFTP but fall back to
587 * scp1 if that fails. This variable is the means by which
588 * scp.c can reach into the SSH code and find out which one it
594 * Used for username and password input.
596 char *userpass_input_buffer
;
597 int userpass_input_buflen
;
598 int userpass_input_bufpos
;
599 int userpass_input_echo
;
601 char *portfwd_strptr
;
607 int v1_throttle_count
;
610 int v1_stdout_throttling
;
611 int v2_outgoing_sequence
;
613 int ssh1_rdpkt_crstate
;
614 int ssh2_rdpkt_crstate
;
615 int do_ssh_init_crstate
;
616 int ssh_gotdata_crstate
;
617 int ssh1_protocol_crstate
;
618 int do_ssh1_login_crstate
;
619 int do_ssh2_transport_crstate
;
620 int do_ssh2_authconn_crstate
;
622 void *do_ssh_init_state
;
623 void *do_ssh1_login_state
;
624 void *do_ssh2_transport_state
;
625 void *do_ssh2_authconn_state
;
627 struct rdpkt1_state_tag rdpkt1_state
;
628 struct rdpkt2_state_tag rdpkt2_state
;
630 void (*protocol
) (Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
);
631 int (*s_rdpkt
) (Ssh ssh
, unsigned char **data
, int *datalen
);
634 * We maintain a full _copy_ of a Config structure here, not
635 * merely a pointer to it. That way, when we're passed a new
636 * one for reconfiguration, we can check the differences and
637 * potentially reconfigure port forwardings etc in mid-session.
642 #define logevent(s) logevent(ssh->frontend, s)
644 /* logevent, only printf-formatted. */
645 static void logeventf(Ssh ssh
, char *fmt
, ...)
651 buf
= dupvprintf(fmt
, ap
);
657 #define bombout(msg) ( ssh->state = SSH_STATE_CLOSED, \
658 (ssh->s ? sk_close(ssh->s), ssh->s = NULL : 0), \
659 logeventf msg, connection_fatal msg )
661 static int ssh_channelcmp(void *av
, void *bv
)
663 struct ssh_channel
*a
= (struct ssh_channel
*) av
;
664 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
665 if (a
->localid
< b
->localid
)
667 if (a
->localid
> b
->localid
)
671 static int ssh_channelfind(void *av
, void *bv
)
673 unsigned *a
= (unsigned *) av
;
674 struct ssh_channel
*b
= (struct ssh_channel
*) bv
;
682 static int ssh_rportcmp_ssh1(void *av
, void *bv
)
684 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
685 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
687 if ( (i
= strcmp(a
->dhost
, b
->dhost
)) != 0)
688 return i
< 0 ?
-1 : +1;
689 if (a
->dport
> b
->dport
)
691 if (a
->dport
< b
->dport
)
696 static int ssh_rportcmp_ssh2(void *av
, void *bv
)
698 struct ssh_rportfwd
*a
= (struct ssh_rportfwd
*) av
;
699 struct ssh_rportfwd
*b
= (struct ssh_rportfwd
*) bv
;
701 if (a
->sport
> b
->sport
)
703 if (a
->sport
< b
->sport
)
708 static int alloc_channel_id(Ssh ssh
)
710 const unsigned CHANNEL_NUMBER_OFFSET
= 256;
711 unsigned low
, high
, mid
;
713 struct ssh_channel
*c
;
716 * First-fit allocation of channel numbers: always pick the
717 * lowest unused one. To do this, binary-search using the
718 * counted B-tree to find the largest channel ID which is in a
719 * contiguous sequence from the beginning. (Precisely
720 * everything in that sequence must have ID equal to its tree
721 * index plus CHANNEL_NUMBER_OFFSET.)
723 tsize
= count234(ssh
->channels
);
727 while (high
- low
> 1) {
728 mid
= (high
+ low
) / 2;
729 c
= index234(ssh
->channels
, mid
);
730 if (c
->localid
== mid
+ CHANNEL_NUMBER_OFFSET
)
731 low
= mid
; /* this one is fine */
733 high
= mid
; /* this one is past it */
736 * Now low points to either -1, or the tree index of the
737 * largest ID in the initial sequence.
740 unsigned i
= low
+ 1 + CHANNEL_NUMBER_OFFSET
;
741 assert(NULL
== find234(ssh
->channels
, &i
, ssh_channelfind
));
743 return low
+ 1 + CHANNEL_NUMBER_OFFSET
;
746 static void c_write(Ssh ssh
, const char *buf
, int len
)
748 if ((flags
& FLAG_STDERR
)) {
750 for (i
= 0; i
< len
; i
++)
752 fputc(buf
[i
], stderr
);
755 from_backend(ssh
->frontend
, 1, buf
, len
);
758 static void c_write_untrusted(Ssh ssh
, const char *buf
, int len
)
761 for (i
= 0; i
< len
; i
++) {
763 c_write(ssh
, "\r\n", 2);
764 else if ((buf
[i
] & 0x60) || (buf
[i
] == '\r'))
765 c_write(ssh
, buf
+ i
, 1);
769 static void c_write_str(Ssh ssh
, const char *buf
)
771 c_write(ssh
, buf
, strlen(buf
));
775 * Collect incoming data in the incoming packet buffer.
776 * Decipher and verify the packet when it is completely read.
777 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
778 * Update the *data and *datalen variables.
779 * Return the additional nr of bytes needed, or 0 when
780 * a complete packet is available.
782 static int ssh1_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
784 struct rdpkt1_state_tag
*st
= &ssh
->rdpkt1_state
;
786 crBegin(ssh
->ssh1_rdpkt_crstate
);
791 ssh
->pktin
.length
= 0;
793 for (st
->i
= st
->len
= 0; st
->i
< 4; st
->i
++) {
794 while ((*datalen
) == 0)
796 st
->len
= (st
->len
<< 8) + **data
;
797 (*data
)++, (*datalen
)--;
800 st
->pad
= 8 - (st
->len
% 8);
801 st
->biglen
= st
->len
+ st
->pad
;
802 ssh
->pktin
.length
= st
->len
- 5;
804 if (ssh
->pktin
.maxlen
< st
->biglen
) {
805 ssh
->pktin
.maxlen
= st
->biglen
;
806 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
, st
->biglen
+ APIEXTRA
);
809 st
->to_read
= st
->biglen
;
810 st
->p
= ssh
->pktin
.data
;
811 while (st
->to_read
> 0) {
812 st
->chunk
= st
->to_read
;
813 while ((*datalen
) == 0)
814 crReturn(st
->to_read
);
815 if (st
->chunk
> (*datalen
))
816 st
->chunk
= (*datalen
);
817 memcpy(st
->p
, *data
, st
->chunk
);
819 *datalen
-= st
->chunk
;
821 st
->to_read
-= st
->chunk
;
824 if (ssh
->cipher
&& detect_attack(ssh
->crcda_ctx
, ssh
->pktin
.data
,
826 bombout((ssh
,"Network attack (CRC compensation) detected!"));
831 ssh
->cipher
->decrypt(ssh
->v1_cipher_ctx
, ssh
->pktin
.data
, st
->biglen
);
833 st
->realcrc
= crc32(ssh
->pktin
.data
, st
->biglen
- 4);
834 st
->gotcrc
= GET_32BIT(ssh
->pktin
.data
+ st
->biglen
- 4);
835 if (st
->gotcrc
!= st
->realcrc
) {
836 bombout((ssh
,"Incorrect CRC received on packet"));
840 ssh
->pktin
.body
= ssh
->pktin
.data
+ st
->pad
+ 1;
842 if (ssh
->v1_compressing
) {
843 unsigned char *decompblk
;
845 zlib_decompress_block(ssh
->sc_comp_ctx
,
846 ssh
->pktin
.body
- 1, ssh
->pktin
.length
+ 1,
847 &decompblk
, &decomplen
);
849 if (ssh
->pktin
.maxlen
< st
->pad
+ decomplen
) {
850 ssh
->pktin
.maxlen
= st
->pad
+ decomplen
;
851 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
,
852 ssh
->pktin
.maxlen
+ APIEXTRA
);
853 ssh
->pktin
.body
= ssh
->pktin
.data
+ st
->pad
+ 1;
856 memcpy(ssh
->pktin
.body
- 1, decompblk
, decomplen
);
858 ssh
->pktin
.length
= decomplen
- 1;
861 ssh
->pktin
.type
= ssh
->pktin
.body
[-1];
864 log_packet(ssh
->logctx
,
865 PKT_INCOMING
, ssh
->pktin
.type
,
866 ssh1_pkt_type(ssh
->pktin
.type
),
867 ssh
->pktin
.body
, ssh
->pktin
.length
);
869 if (ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
870 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
||
871 ssh
->pktin
.type
== SSH1_MSG_DEBUG
||
872 ssh
->pktin
.type
== SSH1_SMSG_AUTH_TIS_CHALLENGE
||
873 ssh
->pktin
.type
== SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
874 long stringlen
= GET_32BIT(ssh
->pktin
.body
);
875 if (stringlen
+ 4 != ssh
->pktin
.length
) {
876 bombout((ssh
,"Received data packet with bogus string length"));
881 if (ssh
->pktin
.type
== SSH1_MSG_DEBUG
) {
882 /* log debug message */
884 int stringlen
= GET_32BIT(ssh
->pktin
.body
);
885 strcpy(buf
, "Remote debug message: ");
888 memcpy(buf
+ 8, ssh
->pktin
.body
+ 4, stringlen
);
889 buf
[8 + stringlen
] = '\0';
892 } else if (ssh
->pktin
.type
== SSH1_MSG_IGNORE
) {
897 if (ssh
->pktin
.type
== SSH1_MSG_DISCONNECT
) {
898 /* log reason code in disconnect message */
900 unsigned msglen
= GET_32BIT(ssh
->pktin
.body
);
902 strcpy(buf
, "Remote sent disconnect: ");
903 nowlen
= strlen(buf
);
904 if (msglen
> sizeof(buf
) - nowlen
- 1)
905 msglen
= sizeof(buf
) - nowlen
- 1;
906 memcpy(buf
+ nowlen
, ssh
->pktin
.body
+ 4, msglen
);
907 buf
[nowlen
+ msglen
] = '\0';
908 /* logevent(buf); (this is now done within the bombout macro) */
909 bombout((ssh
,"Server sent disconnect message:\n\"%s\"", buf
+nowlen
));
916 static int ssh2_rdpkt(Ssh ssh
, unsigned char **data
, int *datalen
)
918 struct rdpkt2_state_tag
*st
= &ssh
->rdpkt2_state
;
920 crBegin(ssh
->ssh2_rdpkt_crstate
);
924 ssh
->pktin
.length
= 0;
926 st
->cipherblk
= ssh
->sccipher
->blksize
;
929 if (st
->cipherblk
< 8)
932 if (ssh
->pktin
.maxlen
< st
->cipherblk
) {
933 ssh
->pktin
.maxlen
= st
->cipherblk
;
934 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
, st
->cipherblk
+ APIEXTRA
);
938 * Acquire and decrypt the first block of the packet. This will
939 * contain the length and padding details.
941 for (st
->i
= st
->len
= 0; st
->i
< st
->cipherblk
; st
->i
++) {
942 while ((*datalen
) == 0)
943 crReturn(st
->cipherblk
- st
->i
);
944 ssh
->pktin
.data
[st
->i
] = *(*data
)++;
949 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
950 ssh
->pktin
.data
, st
->cipherblk
);
953 * Now get the length and padding figures.
955 st
->len
= GET_32BIT(ssh
->pktin
.data
);
956 st
->pad
= ssh
->pktin
.data
[4];
959 * _Completely_ silly lengths should be stomped on before they
960 * do us any more damage.
962 if (st
->len
< 0 || st
->pad
< 0 || st
->len
+ st
->pad
< 0) {
963 bombout((ssh
,"Incoming packet was garbled on decryption"));
968 * This enables us to deduce the payload length.
970 st
->payload
= st
->len
- st
->pad
- 1;
972 ssh
->pktin
.length
= st
->payload
+ 5;
975 * So now we can work out the total packet length.
977 st
->packetlen
= st
->len
+ 4;
978 st
->maclen
= ssh
->scmac ? ssh
->scmac
->len
: 0;
981 * Adjust memory allocation if packet is too big.
983 if (ssh
->pktin
.maxlen
< st
->packetlen
+ st
->maclen
) {
984 ssh
->pktin
.maxlen
= st
->packetlen
+ st
->maclen
;
985 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
,
986 ssh
->pktin
.maxlen
+ APIEXTRA
);
990 * Read and decrypt the remainder of the packet.
992 for (st
->i
= st
->cipherblk
; st
->i
< st
->packetlen
+ st
->maclen
;
994 while ((*datalen
) == 0)
995 crReturn(st
->packetlen
+ st
->maclen
- st
->i
);
996 ssh
->pktin
.data
[st
->i
] = *(*data
)++;
999 /* Decrypt everything _except_ the MAC. */
1001 ssh
->sccipher
->decrypt(ssh
->sc_cipher_ctx
,
1002 ssh
->pktin
.data
+ st
->cipherblk
,
1003 st
->packetlen
- st
->cipherblk
);
1009 && !ssh
->scmac
->verify(ssh
->sc_mac_ctx
, ssh
->pktin
.data
, st
->len
+ 4,
1010 st
->incoming_sequence
)) {
1011 bombout((ssh
,"Incorrect MAC received on packet"));
1014 st
->incoming_sequence
++; /* whether or not we MACed */
1017 * Decompress packet payload.
1020 unsigned char *newpayload
;
1023 ssh
->sccomp
->decompress(ssh
->sc_comp_ctx
,
1024 ssh
->pktin
.data
+ 5, ssh
->pktin
.length
- 5,
1025 &newpayload
, &newlen
)) {
1026 if (ssh
->pktin
.maxlen
< newlen
+ 5) {
1027 ssh
->pktin
.maxlen
= newlen
+ 5;
1028 ssh
->pktin
.data
= srealloc(ssh
->pktin
.data
,
1029 ssh
->pktin
.maxlen
+ APIEXTRA
);
1031 ssh
->pktin
.length
= 5 + newlen
;
1032 memcpy(ssh
->pktin
.data
+ 5, newpayload
, newlen
);
1037 ssh
->pktin
.savedpos
= 6;
1038 ssh
->pktin
.type
= ssh
->pktin
.data
[5];
1041 log_packet(ssh
->logctx
, PKT_INCOMING
, ssh
->pktin
.type
,
1042 ssh2_pkt_type(ssh
->pkt_ctx
, ssh
->pktin
.type
),
1043 ssh
->pktin
.data
+6, ssh
->pktin
.length
-6);
1045 switch (ssh
->pktin
.type
) {
1047 * These packets we must handle instantly.
1049 case SSH2_MSG_DISCONNECT
:
1051 /* log reason code in disconnect message */
1054 int reason
= GET_32BIT(ssh
->pktin
.data
+ 6);
1055 unsigned msglen
= GET_32BIT(ssh
->pktin
.data
+ 10);
1057 if (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) {
1058 buf
= dupprintf("Received disconnect message (%s)",
1059 ssh2_disconnect_reasons
[reason
]);
1061 buf
= dupprintf("Received disconnect message (unknown"
1062 " type %d)", reason
);
1066 buf
= dupprintf("Disconnection message text: %n%.*s",
1067 &nowlen
, msglen
, ssh
->pktin
.data
+ 14);
1069 bombout((ssh
,"Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1071 (reason
> 0 && reason
< lenof(ssh2_disconnect_reasons
)) ?
1072 ssh2_disconnect_reasons
[reason
] : "unknown",
1078 case SSH2_MSG_IGNORE
:
1080 case SSH2_MSG_DEBUG
:
1082 /* log the debug message */
1084 /* int display = ssh->pktin.body[6]; */
1085 int stringlen
= GET_32BIT(ssh
->pktin
.data
+7);
1087 strcpy(buf
, "Remote debug message: ");
1088 prefix
= strlen(buf
);
1089 if (stringlen
> (int)(sizeof(buf
)-prefix
-1))
1090 stringlen
= sizeof(buf
)-prefix
-1;
1091 memcpy(buf
+ prefix
, ssh
->pktin
.data
+ 11, stringlen
);
1092 buf
[prefix
+ stringlen
] = '\0';
1095 goto next_packet
; /* FIXME: print the debug message */
1098 * These packets we need do nothing about here.
1100 case SSH2_MSG_UNIMPLEMENTED
:
1101 case SSH2_MSG_SERVICE_REQUEST
:
1102 case SSH2_MSG_SERVICE_ACCEPT
:
1103 case SSH2_MSG_KEXINIT
:
1104 case SSH2_MSG_NEWKEYS
:
1105 case SSH2_MSG_KEXDH_INIT
:
1106 case SSH2_MSG_KEXDH_REPLY
:
1107 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1108 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1109 case SSH2_MSG_KEX_DH_GEX_INIT
:
1110 case SSH2_MSG_KEX_DH_GEX_REPLY
:
1111 case SSH2_MSG_USERAUTH_REQUEST
:
1112 case SSH2_MSG_USERAUTH_FAILURE
:
1113 case SSH2_MSG_USERAUTH_SUCCESS
:
1114 case SSH2_MSG_USERAUTH_BANNER
:
1115 case SSH2_MSG_USERAUTH_PK_OK
:
1116 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1117 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1118 case SSH2_MSG_USERAUTH_INFO_RESPONSE
:
1119 case SSH2_MSG_GLOBAL_REQUEST
:
1120 case SSH2_MSG_REQUEST_SUCCESS
:
1121 case SSH2_MSG_REQUEST_FAILURE
:
1122 case SSH2_MSG_CHANNEL_OPEN
:
1123 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
:
1124 case SSH2_MSG_CHANNEL_OPEN_FAILURE
:
1125 case SSH2_MSG_CHANNEL_WINDOW_ADJUST
:
1126 case SSH2_MSG_CHANNEL_DATA
:
1127 case SSH2_MSG_CHANNEL_EXTENDED_DATA
:
1128 case SSH2_MSG_CHANNEL_EOF
:
1129 case SSH2_MSG_CHANNEL_CLOSE
:
1130 case SSH2_MSG_CHANNEL_REQUEST
:
1131 case SSH2_MSG_CHANNEL_SUCCESS
:
1132 case SSH2_MSG_CHANNEL_FAILURE
:
1136 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1139 ssh2_pkt_init(ssh
, SSH2_MSG_UNIMPLEMENTED
);
1140 ssh2_pkt_adduint32(ssh
, st
->incoming_sequence
- 1);
1148 static void ssh1_pktout_size(Ssh ssh
, int len
)
1152 len
+= 5; /* type and CRC */
1153 pad
= 8 - (len
% 8);
1156 ssh
->pktout
.length
= len
- 5;
1157 if (ssh
->pktout
.maxlen
< biglen
) {
1158 ssh
->pktout
.maxlen
= biglen
;
1160 /* Allocate enough buffer space for extra block
1161 * for MS CryptEncrypt() */
1162 ssh
->pktout
.data
= srealloc(ssh
->pktout
.data
, biglen
+ 12);
1164 ssh
->pktout
.data
= srealloc(ssh
->pktout
.data
, biglen
+ 4);
1167 ssh
->pktout
.body
= ssh
->pktout
.data
+ 4 + pad
+ 1;
1170 static void s_wrpkt_start(Ssh ssh
, int type
, int len
)
1172 ssh1_pktout_size(ssh
, len
);
1173 ssh
->pktout
.type
= type
;
1176 static int s_wrpkt_prepare(Ssh ssh
)
1182 * XXX various versions of SC (including 8.8.4) screw up the
1183 * register allocation in this function and use the same register
1184 * (D6) for len and as a temporary, with predictable results. The
1185 * following sledgehammer prevents this.
1191 ssh
->pktout
.body
[-1] = ssh
->pktout
.type
;
1194 log_packet(ssh
->logctx
, PKT_OUTGOING
, ssh
->pktout
.type
,
1195 ssh1_pkt_type(ssh
->pktout
.type
),
1196 ssh
->pktout
.body
, ssh
->pktout
.length
);
1198 if (ssh
->v1_compressing
) {
1199 unsigned char *compblk
;
1201 zlib_compress_block(ssh
->cs_comp_ctx
,
1202 ssh
->pktout
.body
- 1, ssh
->pktout
.length
+ 1,
1203 &compblk
, &complen
);
1204 ssh1_pktout_size(ssh
, complen
- 1);
1205 memcpy(ssh
->pktout
.body
- 1, compblk
, complen
);
1209 len
= ssh
->pktout
.length
+ 5; /* type and CRC */
1210 pad
= 8 - (len
% 8);
1213 for (i
= 0; i
< pad
; i
++)
1214 ssh
->pktout
.data
[i
+ 4] = random_byte();
1215 crc
= crc32(ssh
->pktout
.data
+ 4, biglen
- 4);
1216 PUT_32BIT(ssh
->pktout
.data
+ biglen
, crc
);
1217 PUT_32BIT(ssh
->pktout
.data
, len
);
1220 ssh
->cipher
->encrypt(ssh
->v1_cipher_ctx
, ssh
->pktout
.data
+ 4, biglen
);
1225 static void s_wrpkt(Ssh ssh
)
1228 len
= s_wrpkt_prepare(ssh
);
1229 backlog
= sk_write(ssh
->s
, (char *)ssh
->pktout
.data
, len
);
1230 if (backlog
> SSH_MAX_BACKLOG
)
1231 ssh_throttle_all(ssh
, 1, backlog
);
1234 static void s_wrpkt_defer(Ssh ssh
)
1237 len
= s_wrpkt_prepare(ssh
);
1238 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1239 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1240 ssh
->deferred_send_data
= srealloc(ssh
->deferred_send_data
,
1241 ssh
->deferred_size
);
1243 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, ssh
->pktout
.data
, len
);
1244 ssh
->deferred_len
+= len
;
1248 * Construct a packet with the specified contents.
1250 static void construct_packet(Ssh ssh
, int pkttype
, va_list ap1
, va_list ap2
)
1252 unsigned char *p
, *argp
, argchar
;
1253 unsigned long argint
;
1254 int pktlen
, argtype
, arglen
;
1258 while ((argtype
= va_arg(ap1
, int)) != PKT_END
) {
1261 (void) va_arg(ap1
, int);
1265 (void) va_arg(ap1
, int);
1269 (void) va_arg(ap1
, unsigned char *);
1270 arglen
= va_arg(ap1
, int);
1274 argp
= va_arg(ap1
, unsigned char *);
1275 arglen
= strlen((char *)argp
);
1276 pktlen
+= 4 + arglen
;
1279 bn
= va_arg(ap1
, Bignum
);
1280 pktlen
+= ssh1_bignum_length(bn
);
1287 s_wrpkt_start(ssh
, pkttype
, pktlen
);
1288 p
= ssh
->pktout
.body
;
1290 while ((argtype
= va_arg(ap2
, int)) != PKT_END
) {
1293 argint
= va_arg(ap2
, int);
1294 PUT_32BIT(p
, argint
);
1298 argchar
= (unsigned char) va_arg(ap2
, int);
1303 argp
= va_arg(ap2
, unsigned char *);
1304 arglen
= va_arg(ap2
, int);
1305 memcpy(p
, argp
, arglen
);
1309 argp
= va_arg(ap2
, unsigned char *);
1310 arglen
= strlen((char *)argp
);
1311 PUT_32BIT(p
, arglen
);
1312 memcpy(p
+ 4, argp
, arglen
);
1316 bn
= va_arg(ap2
, Bignum
);
1317 p
+= ssh1_write_bignum(p
, bn
);
1323 static void send_packet(Ssh ssh
, int pkttype
, ...)
1326 va_start(ap1
, pkttype
);
1327 va_start(ap2
, pkttype
);
1328 construct_packet(ssh
, pkttype
, ap1
, ap2
);
1332 static void defer_packet(Ssh ssh
, int pkttype
, ...)
1335 va_start(ap1
, pkttype
);
1336 va_start(ap2
, pkttype
);
1337 construct_packet(ssh
, pkttype
, ap1
, ap2
);
1341 static int ssh_versioncmp(char *a
, char *b
)
1344 unsigned long av
, bv
;
1346 av
= strtoul(a
, &ae
, 10);
1347 bv
= strtoul(b
, &be
, 10);
1349 return (av
< bv ?
-1 : +1);
1354 av
= strtoul(ae
, &ae
, 10);
1355 bv
= strtoul(be
, &be
, 10);
1357 return (av
< bv ?
-1 : +1);
1362 * Utility routines for putting an SSH-protocol `string' and
1363 * `uint32' into a SHA state.
1366 static void sha_string(SHA_State
* s
, void *str
, int len
)
1368 unsigned char lenblk
[4];
1369 PUT_32BIT(lenblk
, len
);
1370 SHA_Bytes(s
, lenblk
, 4);
1371 SHA_Bytes(s
, str
, len
);
1374 static void sha_uint32(SHA_State
* s
, unsigned i
)
1376 unsigned char intblk
[4];
1377 PUT_32BIT(intblk
, i
);
1378 SHA_Bytes(s
, intblk
, 4);
1382 * SSH2 packet construction functions.
1384 static void ssh2_pkt_ensure(Ssh ssh
, int length
)
1386 if (ssh
->pktout
.maxlen
< length
) {
1387 ssh
->pktout
.maxlen
= length
+ 256;
1388 ssh
->pktout
.data
= srealloc(ssh
->pktout
.data
,
1389 ssh
->pktout
.maxlen
+ APIEXTRA
);
1390 if (!ssh
->pktout
.data
)
1391 fatalbox("Out of memory");
1394 static void ssh2_pkt_adddata(Ssh ssh
, void *data
, int len
)
1396 ssh
->pktout
.length
+= len
;
1397 ssh2_pkt_ensure(ssh
, ssh
->pktout
.length
);
1398 memcpy(ssh
->pktout
.data
+ ssh
->pktout
.length
- len
, data
, len
);
1400 static void ssh2_pkt_addbyte(Ssh ssh
, unsigned char byte
)
1402 ssh2_pkt_adddata(ssh
, &byte
, 1);
1404 static void ssh2_pkt_init(Ssh ssh
, int pkt_type
)
1406 ssh
->pktout
.length
= 5;
1407 ssh2_pkt_addbyte(ssh
, (unsigned char) pkt_type
);
1409 static void ssh2_pkt_addbool(Ssh ssh
, unsigned char value
)
1411 ssh2_pkt_adddata(ssh
, &value
, 1);
1413 static void ssh2_pkt_adduint32(Ssh ssh
, unsigned long value
)
1416 PUT_32BIT(x
, value
);
1417 ssh2_pkt_adddata(ssh
, x
, 4);
1419 static void ssh2_pkt_addstring_start(Ssh ssh
)
1421 ssh2_pkt_adduint32(ssh
, 0);
1422 ssh
->pktout
.savedpos
= ssh
->pktout
.length
;
1424 static void ssh2_pkt_addstring_str(Ssh ssh
, char *data
)
1426 ssh2_pkt_adddata(ssh
, data
, strlen(data
));
1427 PUT_32BIT(ssh
->pktout
.data
+ ssh
->pktout
.savedpos
- 4,
1428 ssh
->pktout
.length
- ssh
->pktout
.savedpos
);
1430 static void ssh2_pkt_addstring_data(Ssh ssh
, char *data
, int len
)
1432 ssh2_pkt_adddata(ssh
, data
, len
);
1433 PUT_32BIT(ssh
->pktout
.data
+ ssh
->pktout
.savedpos
- 4,
1434 ssh
->pktout
.length
- ssh
->pktout
.savedpos
);
1436 static void ssh2_pkt_addstring(Ssh ssh
, char *data
)
1438 ssh2_pkt_addstring_start(ssh
);
1439 ssh2_pkt_addstring_str(ssh
, data
);
1441 static unsigned char *ssh2_mpint_fmt(Bignum b
, int *len
)
1444 int i
, n
= (bignum_bitcount(b
) + 7) / 8;
1447 fatalbox("out of memory");
1449 for (i
= 1; i
<= n
; i
++)
1450 p
[i
] = bignum_byte(b
, n
- i
);
1452 while (i
<= n
&& p
[i
] == 0 && (p
[i
+ 1] & 0x80) == 0)
1454 memmove(p
, p
+ i
, n
+ 1 - i
);
1458 static void ssh2_pkt_addmp(Ssh ssh
, Bignum b
)
1462 p
= ssh2_mpint_fmt(b
, &len
);
1463 ssh2_pkt_addstring_start(ssh
);
1464 ssh2_pkt_addstring_data(ssh
, (char *)p
, len
);
1469 * Construct an SSH2 final-form packet: compress it, encrypt it,
1470 * put the MAC on it. Final packet, ready to be sent, is stored in
1471 * ssh->pktout.data. Total length is returned.
1473 static int ssh2_pkt_construct(Ssh ssh
)
1475 int cipherblk
, maclen
, padding
, i
;
1478 log_packet(ssh
->logctx
, PKT_OUTGOING
, ssh
->pktout
.data
[5],
1479 ssh2_pkt_type(ssh
->pkt_ctx
, ssh
->pktout
.data
[5]),
1480 ssh
->pktout
.data
+ 6, ssh
->pktout
.length
- 6);
1483 * Compress packet payload.
1486 unsigned char *newpayload
;
1489 ssh
->cscomp
->compress(ssh
->cs_comp_ctx
, ssh
->pktout
.data
+ 5,
1490 ssh
->pktout
.length
- 5,
1491 &newpayload
, &newlen
)) {
1492 ssh
->pktout
.length
= 5;
1493 ssh2_pkt_adddata(ssh
, newpayload
, newlen
);
1499 * Add padding. At least four bytes, and must also bring total
1500 * length (minus MAC) up to a multiple of the block size.
1502 cipherblk
= ssh
->cscipher ? ssh
->cscipher
->blksize
: 8; /* block size */
1503 cipherblk
= cipherblk
< 8 ?
8 : cipherblk
; /* or 8 if blksize < 8 */
1506 (cipherblk
- (ssh
->pktout
.length
+ padding
) % cipherblk
) % cipherblk
;
1507 maclen
= ssh
->csmac ? ssh
->csmac
->len
: 0;
1508 ssh2_pkt_ensure(ssh
, ssh
->pktout
.length
+ padding
+ maclen
);
1509 ssh
->pktout
.data
[4] = padding
;
1510 for (i
= 0; i
< padding
; i
++)
1511 ssh
->pktout
.data
[ssh
->pktout
.length
+ i
] = random_byte();
1512 PUT_32BIT(ssh
->pktout
.data
, ssh
->pktout
.length
+ padding
- 4);
1514 ssh
->csmac
->generate(ssh
->cs_mac_ctx
, ssh
->pktout
.data
,
1515 ssh
->pktout
.length
+ padding
,
1516 ssh
->v2_outgoing_sequence
);
1517 ssh
->v2_outgoing_sequence
++; /* whether or not we MACed */
1520 ssh
->cscipher
->encrypt(ssh
->cs_cipher_ctx
,
1521 ssh
->pktout
.data
, ssh
->pktout
.length
+ padding
);
1523 /* Ready-to-send packet starts at ssh->pktout.data. We return length. */
1524 return ssh
->pktout
.length
+ padding
+ maclen
;
1528 * Construct and send an SSH2 packet immediately.
1530 static void ssh2_pkt_send(Ssh ssh
)
1534 len
= ssh2_pkt_construct(ssh
);
1535 backlog
= sk_write(ssh
->s
, (char *)ssh
->pktout
.data
, len
);
1536 if (backlog
> SSH_MAX_BACKLOG
)
1537 ssh_throttle_all(ssh
, 1, backlog
);
1541 * Construct an SSH2 packet and add it to a deferred data block.
1542 * Useful for sending multiple packets in a single sk_write() call,
1543 * to prevent a traffic-analysing listener from being able to work
1544 * out the length of any particular packet (such as the password
1547 * Note that because SSH2 sequence-numbers its packets, this can
1548 * NOT be used as an m4-style `defer' allowing packets to be
1549 * constructed in one order and sent in another.
1551 static void ssh2_pkt_defer(Ssh ssh
)
1553 int len
= ssh2_pkt_construct(ssh
);
1554 if (ssh
->deferred_len
+ len
> ssh
->deferred_size
) {
1555 ssh
->deferred_size
= ssh
->deferred_len
+ len
+ 128;
1556 ssh
->deferred_send_data
= srealloc(ssh
->deferred_send_data
,
1557 ssh
->deferred_size
);
1559 memcpy(ssh
->deferred_send_data
+ ssh
->deferred_len
, ssh
->pktout
.data
, len
);
1560 ssh
->deferred_len
+= len
;
1564 * Send the whole deferred data block constructed by
1565 * ssh2_pkt_defer() or SSH1's defer_packet().
1567 static void ssh_pkt_defersend(Ssh ssh
)
1570 backlog
= sk_write(ssh
->s
, (char *)ssh
->deferred_send_data
,
1572 ssh
->deferred_len
= ssh
->deferred_size
= 0;
1573 sfree(ssh
->deferred_send_data
);
1574 ssh
->deferred_send_data
= NULL
;
1575 if (backlog
> SSH_MAX_BACKLOG
)
1576 ssh_throttle_all(ssh
, 1, backlog
);
1580 void bndebug(char *string
, Bignum b
)
1584 p
= ssh2_mpint_fmt(b
, &len
);
1585 debug(("%s", string
));
1586 for (i
= 0; i
< len
; i
++)
1587 debug((" %02x", p
[i
]));
1593 static void sha_mpint(SHA_State
* s
, Bignum b
)
1597 p
= ssh2_mpint_fmt(b
, &len
);
1598 sha_string(s
, p
, len
);
1603 * SSH2 packet decode functions.
1605 static unsigned long ssh2_pkt_getuint32(Ssh ssh
)
1607 unsigned long value
;
1608 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 4)
1609 return 0; /* arrgh, no way to decline (FIXME?) */
1610 value
= GET_32BIT(ssh
->pktin
.data
+ ssh
->pktin
.savedpos
);
1611 ssh
->pktin
.savedpos
+= 4;
1614 static int ssh2_pkt_getbool(Ssh ssh
)
1616 unsigned long value
;
1617 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 1)
1618 return 0; /* arrgh, no way to decline (FIXME?) */
1619 value
= ssh
->pktin
.data
[ssh
->pktin
.savedpos
] != 0;
1620 ssh
->pktin
.savedpos
++;
1623 static void ssh2_pkt_getstring(Ssh ssh
, char **p
, int *length
)
1628 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< 4)
1630 len
= GET_32BIT(ssh
->pktin
.data
+ ssh
->pktin
.savedpos
);
1634 ssh
->pktin
.savedpos
+= 4;
1635 if (ssh
->pktin
.length
- ssh
->pktin
.savedpos
< *length
)
1637 *p
= (char *)(ssh
->pktin
.data
+ ssh
->pktin
.savedpos
);
1638 ssh
->pktin
.savedpos
+= *length
;
1640 static Bignum
ssh2_pkt_getmp(Ssh ssh
)
1646 ssh2_pkt_getstring(ssh
, &p
, &length
);
1650 bombout((ssh
,"internal error: Can't handle negative mpints"));
1653 b
= bignum_from_bytes((unsigned char *)p
, length
);
1658 * Helper function to add an SSH2 signature blob to a packet.
1659 * Expects to be shown the public key blob as well as the signature
1660 * blob. Normally works just like ssh2_pkt_addstring, but will
1661 * fiddle with the signature packet if necessary for
1662 * BUG_SSH2_RSA_PADDING.
1664 static void ssh2_add_sigblob(Ssh ssh
, void *pkblob_v
, int pkblob_len
,
1665 void *sigblob_v
, int sigblob_len
)
1667 unsigned char *pkblob
= (unsigned char *)pkblob_v
;
1668 unsigned char *sigblob
= (unsigned char *)sigblob_v
;
1670 /* dmemdump(pkblob, pkblob_len); */
1671 /* dmemdump(sigblob, sigblob_len); */
1674 * See if this is in fact an ssh-rsa signature and a buggy
1675 * server; otherwise we can just do this the easy way.
1677 if ((ssh
->remote_bugs
& BUG_SSH2_RSA_PADDING
) &&
1678 (GET_32BIT(pkblob
) == 7 && !memcmp(pkblob
+4, "ssh-rsa", 7))) {
1679 int pos
, len
, siglen
;
1682 * Find the byte length of the modulus.
1685 pos
= 4+7; /* skip over "ssh-rsa" */
1686 pos
+= 4 + GET_32BIT(pkblob
+pos
); /* skip over exponent */
1687 len
= GET_32BIT(pkblob
+pos
); /* find length of modulus */
1688 pos
+= 4; /* find modulus itself */
1689 while (len
> 0 && pkblob
[pos
] == 0)
1691 /* debug(("modulus length is %d\n", len)); */
1694 * Now find the signature integer.
1696 pos
= 4+7; /* skip over "ssh-rsa" */
1697 siglen
= GET_32BIT(sigblob
+pos
);
1698 /* debug(("signature length is %d\n", siglen)); */
1700 if (len
!= siglen
) {
1701 unsigned char newlen
[4];
1702 ssh2_pkt_addstring_start(ssh
);
1703 ssh2_pkt_addstring_data(ssh
, (char *)sigblob
, pos
);
1704 /* dmemdump(sigblob, pos); */
1705 pos
+= 4; /* point to start of actual sig */
1706 PUT_32BIT(newlen
, len
);
1707 ssh2_pkt_addstring_data(ssh
, (char *)newlen
, 4);
1708 /* dmemdump(newlen, 4); */
1710 while (len
-- > siglen
) {
1711 ssh2_pkt_addstring_data(ssh
, (char *)newlen
, 1);
1712 /* dmemdump(newlen, 1); */
1714 ssh2_pkt_addstring_data(ssh
, (char *)(sigblob
+pos
), siglen
);
1715 /* dmemdump(sigblob+pos, siglen); */
1719 /* Otherwise fall through and do it the easy way. */
1722 ssh2_pkt_addstring_start(ssh
);
1723 ssh2_pkt_addstring_data(ssh
, (char *)sigblob
, sigblob_len
);
1727 * Examine the remote side's version string and compare it against
1728 * a list of known buggy implementations.
1730 static void ssh_detect_bugs(Ssh ssh
, char *vstring
)
1732 char *imp
; /* pointer to implementation part */
1734 imp
+= strcspn(imp
, "-");
1736 imp
+= strcspn(imp
, "-");
1739 ssh
->remote_bugs
= 0;
1741 if (ssh
->cfg
.sshbug_ignore1
== FORCE_ON
||
1742 (ssh
->cfg
.sshbug_ignore1
== AUTO
&&
1743 (!strcmp(imp
, "1.2.18") || !strcmp(imp
, "1.2.19") ||
1744 !strcmp(imp
, "1.2.20") || !strcmp(imp
, "1.2.21") ||
1745 !strcmp(imp
, "1.2.22") || !strcmp(imp
, "Cisco-1.25")))) {
1747 * These versions don't support SSH1_MSG_IGNORE, so we have
1748 * to use a different defence against password length
1751 ssh
->remote_bugs
|= BUG_CHOKES_ON_SSH1_IGNORE
;
1752 logevent("We believe remote version has SSH1 ignore bug");
1755 if (ssh
->cfg
.sshbug_plainpw1
== FORCE_ON
||
1756 (ssh
->cfg
.sshbug_plainpw1
== AUTO
&&
1757 (!strcmp(imp
, "Cisco-1.25")))) {
1759 * These versions need a plain password sent; they can't
1760 * handle having a null and a random length of data after
1763 ssh
->remote_bugs
|= BUG_NEEDS_SSH1_PLAIN_PASSWORD
;
1764 logevent("We believe remote version needs a plain SSH1 password");
1767 if (ssh
->cfg
.sshbug_rsa1
== FORCE_ON
||
1768 (ssh
->cfg
.sshbug_rsa1
== AUTO
&&
1769 (!strcmp(imp
, "Cisco-1.25")))) {
1771 * These versions apparently have no clue whatever about
1772 * RSA authentication and will panic and die if they see
1773 * an AUTH_RSA message.
1775 ssh
->remote_bugs
|= BUG_CHOKES_ON_RSA
;
1776 logevent("We believe remote version can't handle RSA authentication");
1779 if (ssh
->cfg
.sshbug_hmac2
== FORCE_ON
||
1780 (ssh
->cfg
.sshbug_hmac2
== AUTO
&&
1781 (wc_match("2.1.0*", imp
) || wc_match("2.0.*", imp
) ||
1782 wc_match("2.2.0*", imp
) || wc_match("2.3.0*", imp
) ||
1783 wc_match("2.1 *", imp
)))) {
1785 * These versions have the HMAC bug.
1787 ssh
->remote_bugs
|= BUG_SSH2_HMAC
;
1788 logevent("We believe remote version has SSH2 HMAC bug");
1791 if (ssh
->cfg
.sshbug_derivekey2
== FORCE_ON
||
1792 (ssh
->cfg
.sshbug_derivekey2
== AUTO
&&
1793 (wc_match("2.0.0*", imp
) || wc_match("2.0.10*", imp
) ))) {
1795 * These versions have the key-derivation bug (failing to
1796 * include the literal shared secret in the hashes that
1797 * generate the keys).
1799 ssh
->remote_bugs
|= BUG_SSH2_DERIVEKEY
;
1800 logevent("We believe remote version has SSH2 key-derivation bug");
1803 if (ssh
->cfg
.sshbug_rsapad2
== FORCE_ON
||
1804 (ssh
->cfg
.sshbug_rsapad2
== AUTO
&&
1805 (wc_match("OpenSSH_2.[5-9]*", imp
) ||
1806 wc_match("OpenSSH_3.[0-2]*", imp
)))) {
1808 * These versions have the SSH2 RSA padding bug.
1810 ssh
->remote_bugs
|= BUG_SSH2_RSA_PADDING
;
1811 logevent("We believe remote version has SSH2 RSA padding bug");
1814 if (ssh
->cfg
.sshbug_pksessid2
== FORCE_ON
||
1815 (ssh
->cfg
.sshbug_pksessid2
== AUTO
&&
1816 wc_match("OpenSSH_2.[0-2]*", imp
))) {
1818 * These versions have the SSH2 session-ID bug in
1819 * public-key authentication.
1821 ssh
->remote_bugs
|= BUG_SSH2_PK_SESSIONID
;
1822 logevent("We believe remote version has SSH2 public-key-session-ID bug");
1825 if (ssh
->cfg
.sshbug_dhgex2
== FORCE_ON
) {
1827 * User specified the SSH2 DH GEX bug.
1829 ssh
->remote_bugs
|= BUG_SSH2_DH_GEX
;
1830 logevent("We believe remote version has SSH2 DH group exchange bug");
1834 static int do_ssh_init(Ssh ssh
, unsigned char c
)
1836 struct do_ssh_init_state
{
1844 crState(do_ssh_init_state
);
1846 crBegin(ssh
->do_ssh_init_crstate
);
1848 /* Search for the string "SSH-" in the input. */
1851 static const int transS
[] = { 1, 2, 2, 1 };
1852 static const int transH
[] = { 0, 0, 3, 0 };
1853 static const int transminus
[] = { 0, 0, 0, -1 };
1855 s
->i
= transS
[s
->i
];
1857 s
->i
= transH
[s
->i
];
1859 s
->i
= transminus
[s
->i
];
1864 crReturn(1); /* get another character */
1868 s
->vstring
= smalloc(s
->vstrsize
);
1869 strcpy(s
->vstring
, "SSH-");
1873 crReturn(1); /* get another char */
1874 if (s
->vslen
>= s
->vstrsize
- 1) {
1876 s
->vstring
= srealloc(s
->vstring
, s
->vstrsize
);
1878 s
->vstring
[s
->vslen
++] = c
;
1881 s
->version
[s
->i
] = '\0';
1883 } else if (s
->i
< sizeof(s
->version
) - 1)
1884 s
->version
[s
->i
++] = c
;
1885 } else if (c
== '\012')
1889 ssh
->agentfwd_enabled
= FALSE
;
1890 ssh
->rdpkt2_state
.incoming_sequence
= 0;
1892 s
->vstring
[s
->vslen
] = 0;
1893 s
->vstring
[strcspn(s
->vstring
, "\r\n")] = '\0';/* remove EOL chars */
1896 vlog
= smalloc(20 + s
->vslen
);
1897 sprintf(vlog
, "Server version: %s", s
->vstring
);
1901 ssh_detect_bugs(ssh
, s
->vstring
);
1904 * Decide which SSH protocol version to support.
1907 /* Anything strictly below "2.0" means protocol 1 is supported. */
1908 s
->proto1
= ssh_versioncmp(s
->version
, "2.0") < 0;
1909 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
1910 s
->proto2
= ssh_versioncmp(s
->version
, "1.99") >= 0;
1912 if (ssh
->cfg
.sshprot
== 0 && !s
->proto1
) {
1913 bombout((ssh
,"SSH protocol version 1 required by user but not provided by server"));
1916 if (ssh
->cfg
.sshprot
== 3 && !s
->proto2
) {
1917 bombout((ssh
,"SSH protocol version 2 required by user but not provided by server"));
1921 if (s
->proto2
&& (ssh
->cfg
.sshprot
>= 2 || !s
->proto1
)) {
1925 char verstring
[80], vlog
[100];
1926 sprintf(verstring
, "SSH-2.0-%s", sshver
);
1927 SHA_Init(&ssh
->exhashbase
);
1929 * Hash our version string and their version string.
1931 sha_string(&ssh
->exhashbase
, verstring
, strlen(verstring
));
1932 sha_string(&ssh
->exhashbase
, s
->vstring
, strcspn(s
->vstring
, "\r\n"));
1933 sprintf(vlog
, "We claim version: %s", verstring
);
1935 strcat(verstring
, "\012");
1936 logevent("Using SSH protocol version 2");
1937 sk_write(ssh
->s
, verstring
, strlen(verstring
));
1938 ssh
->protocol
= ssh2_protocol
;
1940 ssh
->s_rdpkt
= ssh2_rdpkt
;
1945 char verstring
[80], vlog
[100];
1946 sprintf(verstring
, "SSH-%s-%s",
1947 (ssh_versioncmp(s
->version
, "1.5") <= 0 ? s
->version
: "1.5"),
1949 sprintf(vlog
, "We claim version: %s", verstring
);
1951 strcat(verstring
, "\012");
1953 logevent("Using SSH protocol version 1");
1954 sk_write(ssh
->s
, verstring
, strlen(verstring
));
1955 ssh
->protocol
= ssh1_protocol
;
1957 ssh
->s_rdpkt
= ssh1_rdpkt
;
1959 ssh
->state
= SSH_STATE_BEFORE_SIZE
;
1966 static void ssh_gotdata(Ssh ssh
, unsigned char *data
, int datalen
)
1968 crBegin(ssh
->ssh_gotdata_crstate
);
1971 * To begin with, feed the characters one by one to the
1972 * protocol initialisation / selection function do_ssh_init().
1973 * When that returns 0, we're done with the initial greeting
1974 * exchange and can move on to packet discipline.
1977 int ret
; /* need not be kept across crReturn */
1979 crReturnV
; /* more data please */
1980 ret
= do_ssh_init(ssh
, *data
);
1988 * We emerge from that loop when the initial negotiation is
1989 * over and we have selected an s_rdpkt function. Now pass
1990 * everything to s_rdpkt, and then pass the resulting packets
1991 * to the proper protocol handler.
1996 while (datalen
> 0) {
1997 if (ssh
->s_rdpkt(ssh
, &data
, &datalen
) == 0) {
1998 if (ssh
->state
== SSH_STATE_CLOSED
) {
2001 ssh
->protocol(ssh
, NULL
, 0, 1);
2002 if (ssh
->state
== SSH_STATE_CLOSED
) {
2012 static int ssh_closing(Plug plug
, char *error_msg
, int error_code
,
2015 Ssh ssh
= (Ssh
) plug
;
2016 ssh
->state
= SSH_STATE_CLOSED
;
2022 /* A socket error has occurred. */
2023 logevent(error_msg
);
2024 connection_fatal(ssh
->frontend
, error_msg
);
2026 /* Otherwise, the remote side closed the connection normally. */
2031 static int ssh_receive(Plug plug
, int urgent
, char *data
, int len
)
2033 Ssh ssh
= (Ssh
) plug
;
2034 ssh_gotdata(ssh
, (unsigned char *)data
, len
);
2035 if (ssh
->state
== SSH_STATE_CLOSED
) {
2045 static void ssh_sent(Plug plug
, int bufsize
)
2047 Ssh ssh
= (Ssh
) plug
;
2049 * If the send backlog on the SSH socket itself clears, we
2050 * should unthrottle the whole world if it was throttled.
2052 if (bufsize
< SSH_MAX_BACKLOG
)
2053 ssh_throttle_all(ssh
, 0, bufsize
);
2057 * Connect to specified host and port.
2058 * Returns an error message, or NULL on success.
2059 * Also places the canonical host name into `realhost'. It must be
2060 * freed by the caller.
2062 static char *connect_to_host(Ssh ssh
, char *host
, int port
,
2063 char **realhost
, int nodelay
)
2065 static const struct plug_function_table fn_table
= {
2075 ssh
->savedhost
= smalloc(1 + strlen(host
));
2076 if (!ssh
->savedhost
)
2077 fatalbox("Out of memory");
2078 strcpy(ssh
->savedhost
, host
);
2081 port
= 22; /* default ssh port */
2082 ssh
->savedport
= port
;
2087 logeventf(ssh
, "Looking up host \"%s\"", host
);
2088 addr
= name_lookup(host
, port
, realhost
, &ssh
->cfg
);
2089 if ((err
= sk_addr_error(addr
)) != NULL
)
2097 sk_getaddr(addr
, addrbuf
, 100);
2098 logeventf(ssh
, "Connecting to %s port %d", addrbuf
, port
);
2100 ssh
->fn
= &fn_table
;
2101 ssh
->s
= new_connection(addr
, *realhost
, port
,
2102 0, 1, nodelay
, (Plug
) ssh
, &ssh
->cfg
);
2103 if ((err
= sk_socket_error(ssh
->s
)) != NULL
) {
2112 * Throttle or unthrottle the SSH connection.
2114 static void ssh1_throttle(Ssh ssh
, int adjust
)
2116 int old_count
= ssh
->v1_throttle_count
;
2117 ssh
->v1_throttle_count
+= adjust
;
2118 assert(ssh
->v1_throttle_count
>= 0);
2119 if (ssh
->v1_throttle_count
&& !old_count
) {
2120 sk_set_frozen(ssh
->s
, 1);
2121 } else if (!ssh
->v1_throttle_count
&& old_count
) {
2122 sk_set_frozen(ssh
->s
, 0);
2127 * Throttle or unthrottle _all_ local data streams (for when sends
2128 * on the SSH connection itself back up).
2130 static void ssh_throttle_all(Ssh ssh
, int enable
, int bufsize
)
2133 struct ssh_channel
*c
;
2135 if (enable
== ssh
->throttled_all
)
2137 ssh
->throttled_all
= enable
;
2138 ssh
->overall_bufsize
= bufsize
;
2141 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
2143 case CHAN_MAINSESSION
:
2145 * This is treated separately, outside the switch.
2149 x11_override_throttle(c
->u
.x11
.s
, enable
);
2152 /* Agent channels require no buffer management. */
2155 pfd_override_throttle(c
->u
.x11
.s
, enable
);
2162 * Username and password input, abstracted off into routines
2163 * reusable in several places - even between SSH1 and SSH2.
2166 /* Set up a username or password input loop on a given buffer. */
2167 static void setup_userpass_input(Ssh ssh
, char *buffer
, int buflen
, int echo
)
2169 ssh
->userpass_input_buffer
= buffer
;
2170 ssh
->userpass_input_buflen
= buflen
;
2171 ssh
->userpass_input_bufpos
= 0;
2172 ssh
->userpass_input_echo
= echo
;
2176 * Process some terminal data in the course of username/password
2177 * input. Returns >0 for success (line of input returned in
2178 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2179 * for inconclusive (keep waiting for more input please).
2181 static int process_userpass_input(Ssh ssh
, unsigned char *in
, int inlen
)
2186 switch (c
= *in
++) {
2189 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
] = 0;
2190 ssh
->userpass_input_buffer
[ssh
->userpass_input_buflen
-1] = 0;
2195 if (ssh
->userpass_input_bufpos
> 0) {
2196 if (ssh
->userpass_input_echo
)
2197 c_write_str(ssh
, "\b \b");
2198 ssh
->userpass_input_bufpos
--;
2203 while (ssh
->userpass_input_bufpos
> 0) {
2204 if (ssh
->userpass_input_echo
)
2205 c_write_str(ssh
, "\b \b");
2206 ssh
->userpass_input_bufpos
--;
2215 * This simplistic check for printability is disabled
2216 * when we're doing password input, because some people
2217 * have control characters in their passwords.o
2219 if ((!ssh
->userpass_input_echo
||
2220 (c
>= ' ' && c
<= '~') ||
2221 ((unsigned char) c
>= 160))
2222 && ssh
->userpass_input_bufpos
< ssh
->userpass_input_buflen
-1) {
2223 ssh
->userpass_input_buffer
[ssh
->userpass_input_bufpos
++] = c
;
2224 if (ssh
->userpass_input_echo
)
2225 c_write(ssh
, &c
, 1);
2234 * Handle the key exchange and user authentication phases.
2236 static int do_ssh1_login(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
2239 unsigned char cookie
[8];
2240 struct RSAKey servkey
, hostkey
;
2241 struct MD5Context md5c
;
2242 struct do_ssh1_login_state
{
2244 unsigned char *rsabuf
, *keystr1
, *keystr2
;
2245 unsigned long supported_ciphers_mask
, supported_auths_mask
;
2246 int tried_publickey
, tried_agent
;
2247 int tis_auth_refused
, ccard_auth_refused
;
2248 unsigned char session_id
[16];
2251 void *publickey_blob
;
2252 int publickey_bloblen
;
2258 unsigned char request
[5], *response
, *p
;
2267 crState(do_ssh1_login_state
);
2269 crBegin(ssh
->do_ssh1_login_crstate
);
2274 if (ssh
->pktin
.type
!= SSH1_SMSG_PUBLIC_KEY
) {
2275 bombout((ssh
,"Public key packet not received"));
2279 logevent("Received public keys");
2281 memcpy(cookie
, ssh
->pktin
.body
, 8);
2283 i
= makekey(ssh
->pktin
.body
+ 8, &servkey
, &s
->keystr1
, 0);
2284 j
= makekey(ssh
->pktin
.body
+ 8 + i
, &hostkey
, &s
->keystr2
, 0);
2287 * Log the host key fingerprint.
2291 logevent("Host key fingerprint is:");
2292 strcpy(logmsg
, " ");
2293 hostkey
.comment
= NULL
;
2294 rsa_fingerprint(logmsg
+ strlen(logmsg
),
2295 sizeof(logmsg
) - strlen(logmsg
), &hostkey
);
2299 ssh
->v1_remote_protoflags
= GET_32BIT(ssh
->pktin
.body
+ 8 + i
+ j
);
2300 s
->supported_ciphers_mask
= GET_32BIT(ssh
->pktin
.body
+ 12 + i
+ j
);
2301 s
->supported_auths_mask
= GET_32BIT(ssh
->pktin
.body
+ 16 + i
+ j
);
2303 ssh
->v1_local_protoflags
=
2304 ssh
->v1_remote_protoflags
& SSH1_PROTOFLAGS_SUPPORTED
;
2305 ssh
->v1_local_protoflags
|= SSH1_PROTOFLAG_SCREEN_NUMBER
;
2308 MD5Update(&md5c
, s
->keystr2
, hostkey
.bytes
);
2309 MD5Update(&md5c
, s
->keystr1
, servkey
.bytes
);
2310 MD5Update(&md5c
, ssh
->pktin
.body
, 8);
2311 MD5Final(s
->session_id
, &md5c
);
2313 for (i
= 0; i
< 32; i
++)
2314 ssh
->session_key
[i
] = random_byte();
2316 s
->len
= (hostkey
.bytes
> servkey
.bytes ? hostkey
.bytes
: servkey
.bytes
);
2318 s
->rsabuf
= smalloc(s
->len
);
2320 fatalbox("Out of memory");
2323 * Verify the host key.
2327 * First format the key into a string.
2329 int len
= rsastr_len(&hostkey
);
2330 char fingerprint
[100];
2331 char *keystr
= smalloc(len
);
2333 fatalbox("Out of memory");
2334 rsastr_fmt(keystr
, &hostkey
);
2335 rsa_fingerprint(fingerprint
, sizeof(fingerprint
), &hostkey
);
2336 verify_ssh_host_key(ssh
->frontend
,
2337 ssh
->savedhost
, ssh
->savedport
, "rsa", keystr
,
2342 for (i
= 0; i
< 32; i
++) {
2343 s
->rsabuf
[i
] = ssh
->session_key
[i
];
2345 s
->rsabuf
[i
] ^= s
->session_id
[i
];
2348 if (hostkey
.bytes
> servkey
.bytes
) {
2349 rsaencrypt(s
->rsabuf
, 32, &servkey
);
2350 rsaencrypt(s
->rsabuf
, servkey
.bytes
, &hostkey
);
2352 rsaencrypt(s
->rsabuf
, 32, &hostkey
);
2353 rsaencrypt(s
->rsabuf
, hostkey
.bytes
, &servkey
);
2356 logevent("Encrypted session key");
2359 int cipher_chosen
= 0, warn
= 0;
2360 char *cipher_string
= NULL
;
2362 for (i
= 0; !cipher_chosen
&& i
< CIPHER_MAX
; i
++) {
2363 int next_cipher
= ssh
->cfg
.ssh_cipherlist
[i
];
2364 if (next_cipher
== CIPHER_WARN
) {
2365 /* If/when we choose a cipher, warn about it */
2367 } else if (next_cipher
== CIPHER_AES
) {
2368 /* XXX Probably don't need to mention this. */
2369 logevent("AES not supported in SSH1, skipping");
2371 switch (next_cipher
) {
2372 case CIPHER_3DES
: s
->cipher_type
= SSH_CIPHER_3DES
;
2373 cipher_string
= "3DES"; break;
2374 case CIPHER_BLOWFISH
: s
->cipher_type
= SSH_CIPHER_BLOWFISH
;
2375 cipher_string
= "Blowfish"; break;
2376 case CIPHER_DES
: s
->cipher_type
= SSH_CIPHER_DES
;
2377 cipher_string
= "single-DES"; break;
2379 if (s
->supported_ciphers_mask
& (1 << s
->cipher_type
))
2383 if (!cipher_chosen
) {
2384 if ((s
->supported_ciphers_mask
& (1 << SSH_CIPHER_3DES
)) == 0)
2385 bombout((ssh
,"Server violates SSH 1 protocol by not "
2386 "supporting 3DES encryption"));
2388 /* shouldn't happen */
2389 bombout((ssh
,"No supported ciphers found"));
2393 /* Warn about chosen cipher if necessary. */
2395 askcipher(ssh
->frontend
, cipher_string
, 0);
2398 switch (s
->cipher_type
) {
2399 case SSH_CIPHER_3DES
:
2400 logevent("Using 3DES encryption");
2402 case SSH_CIPHER_DES
:
2403 logevent("Using single-DES encryption");
2405 case SSH_CIPHER_BLOWFISH
:
2406 logevent("Using Blowfish encryption");
2410 send_packet(ssh
, SSH1_CMSG_SESSION_KEY
,
2411 PKT_CHAR
, s
->cipher_type
,
2412 PKT_DATA
, cookie
, 8,
2413 PKT_CHAR
, (s
->len
* 8) >> 8, PKT_CHAR
, (s
->len
* 8) & 0xFF,
2414 PKT_DATA
, s
->rsabuf
, s
->len
,
2415 PKT_INT
, ssh
->v1_local_protoflags
, PKT_END
);
2417 logevent("Trying to enable encryption...");
2421 ssh
->cipher
= (s
->cipher_type
== SSH_CIPHER_BLOWFISH ?
&ssh_blowfish_ssh1
:
2422 s
->cipher_type
== SSH_CIPHER_DES ?
&ssh_des
:
2424 ssh
->v1_cipher_ctx
= ssh
->cipher
->make_context();
2425 ssh
->cipher
->sesskey(ssh
->v1_cipher_ctx
, ssh
->session_key
);
2426 logeventf(ssh
, "Initialised %s encryption", ssh
->cipher
->text_name
);
2428 ssh
->crcda_ctx
= crcda_make_context();
2429 logevent("Installing CRC compensation attack detector");
2433 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2434 bombout((ssh
,"Encryption not successfully enabled"));
2438 logevent("Successfully started encryption");
2442 if ((flags
& FLAG_INTERACTIVE
) && !*ssh
->cfg
.username
) {
2443 if (ssh_get_line
&& !ssh_getline_pw_only
) {
2444 if (!ssh_get_line("login as: ",
2445 s
->username
, sizeof(s
->username
), FALSE
)) {
2447 * get_line failed to get a username.
2450 logevent("No username provided. Abandoning session.");
2451 ssh
->state
= SSH_STATE_CLOSED
;
2455 int ret
; /* need not be kept over crReturn */
2456 c_write_str(ssh
, "login as: ");
2459 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
2461 crWaitUntil(!ispkt
);
2462 ret
= process_userpass_input(ssh
, in
, inlen
);
2466 c_write_str(ssh
, "\r\n");
2469 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
2470 s
->username
[sizeof(s
->username
)-1] = '\0';
2473 send_packet(ssh
, SSH1_CMSG_USER
, PKT_STR
, s
->username
, PKT_END
);
2475 char userlog
[22 + sizeof(s
->username
)];
2476 sprintf(userlog
, "Sent username \"%s\"", s
->username
);
2478 if (flags
& FLAG_INTERACTIVE
&&
2479 (!((flags
& FLAG_STDERR
) && (flags
& FLAG_VERBOSE
)))) {
2480 strcat(userlog
, "\r\n");
2481 c_write_str(ssh
, userlog
);
2488 if ((ssh
->remote_bugs
& BUG_CHOKES_ON_RSA
)) {
2489 /* We must not attempt PK auth. Pretend we've already tried it. */
2490 s
->tried_publickey
= s
->tried_agent
= 1;
2492 s
->tried_publickey
= s
->tried_agent
= 0;
2494 s
->tis_auth_refused
= s
->ccard_auth_refused
= 0;
2495 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
2496 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
2497 if (!rsakey_pubblob(&ssh
->cfg
.keyfile
,
2498 &s
->publickey_blob
, &s
->publickey_bloblen
))
2499 s
->publickey_blob
= NULL
;
2501 s
->publickey_blob
= NULL
;
2503 while (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2504 s
->pwpkt_type
= SSH1_CMSG_AUTH_PASSWORD
;
2506 if (agent_exists() && !s
->tried_agent
) {
2508 * Attempt RSA authentication using Pageant.
2514 logevent("Pageant is running. Requesting keys.");
2516 /* Request the keys held by the agent. */
2517 PUT_32BIT(s
->request
, 1);
2518 s
->request
[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES
;
2519 agent_query(s
->request
, 5, &r
, &s
->responselen
);
2520 s
->response
= (unsigned char *) r
;
2521 if (s
->response
&& s
->responselen
>= 5 &&
2522 s
->response
[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER
) {
2523 s
->p
= s
->response
+ 5;
2524 s
->nkeys
= GET_32BIT(s
->p
);
2528 sprintf(buf
, "Pageant has %d SSH1 keys", s
->nkeys
);
2531 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
2534 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
2537 if (s
->publickey_blob
&&
2538 !memcmp(s
->p
, s
->publickey_blob
,
2539 s
->publickey_bloblen
)) {
2540 logevent("This key matches configured key file");
2541 s
->tried_publickey
= 1;
2544 s
->p
+= ssh1_read_bignum(s
->p
, &s
->key
.exponent
);
2545 s
->p
+= ssh1_read_bignum(s
->p
, &s
->key
.modulus
);
2546 s
->commentlen
= GET_32BIT(s
->p
);
2548 s
->commentp
= (char *)s
->p
;
2549 s
->p
+= s
->commentlen
;
2550 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
2551 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
2553 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2554 logevent("Key refused");
2557 logevent("Received RSA challenge");
2558 ssh1_read_bignum(ssh
->pktin
.body
, &s
->challenge
);
2560 char *agentreq
, *q
, *ret
;
2563 len
= 1 + 4; /* message type, bit count */
2564 len
+= ssh1_bignum_length(s
->key
.exponent
);
2565 len
+= ssh1_bignum_length(s
->key
.modulus
);
2566 len
+= ssh1_bignum_length(s
->challenge
);
2567 len
+= 16; /* session id */
2568 len
+= 4; /* response format */
2569 agentreq
= smalloc(4 + len
);
2570 PUT_32BIT(agentreq
, len
);
2572 *q
++ = SSH1_AGENTC_RSA_CHALLENGE
;
2573 PUT_32BIT(q
, bignum_bitcount(s
->key
.modulus
));
2575 q
+= ssh1_write_bignum(q
, s
->key
.exponent
);
2576 q
+= ssh1_write_bignum(q
, s
->key
.modulus
);
2577 q
+= ssh1_write_bignum(q
, s
->challenge
);
2578 memcpy(q
, s
->session_id
, 16);
2580 PUT_32BIT(q
, 1); /* response format */
2581 agent_query(agentreq
, len
+ 4, &vret
, &retlen
);
2585 if (ret
[4] == SSH1_AGENT_RSA_RESPONSE
) {
2586 logevent("Sending Pageant's response");
2587 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
2588 PKT_DATA
, ret
+ 5, 16,
2592 if (ssh
->pktin
.type
== SSH1_SMSG_SUCCESS
) {
2594 ("Pageant's response accepted");
2595 if (flags
& FLAG_VERBOSE
) {
2596 c_write_str(ssh
, "Authenticated using"
2598 c_write(ssh
, s
->commentp
,
2600 c_write_str(ssh
, "\" from agent\r\n");
2605 ("Pageant's response not accepted");
2608 ("Pageant failed to answer challenge");
2612 logevent("No reply received from Pageant");
2615 freebn(s
->key
.exponent
);
2616 freebn(s
->key
.modulus
);
2617 freebn(s
->challenge
);
2625 if (!filename_is_null(ssh
->cfg
.keyfile
) && !s
->tried_publickey
)
2626 s
->pwpkt_type
= SSH1_CMSG_AUTH_RSA
;
2628 if (ssh
->cfg
.try_tis_auth
&&
2629 (s
->supported_auths_mask
& (1 << SSH1_AUTH_TIS
)) &&
2630 !s
->tis_auth_refused
) {
2631 s
->pwpkt_type
= SSH1_CMSG_AUTH_TIS_RESPONSE
;
2632 logevent("Requested TIS authentication");
2633 send_packet(ssh
, SSH1_CMSG_AUTH_TIS
, PKT_END
);
2635 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_TIS_CHALLENGE
) {
2636 logevent("TIS authentication declined");
2637 if (flags
& FLAG_INTERACTIVE
)
2638 c_write_str(ssh
, "TIS authentication refused.\r\n");
2639 s
->tis_auth_refused
= 1;
2642 int challengelen
= GET_32BIT(ssh
->pktin
.body
);
2643 logevent("Received TIS challenge");
2644 if (challengelen
> sizeof(s
->prompt
) - 1)
2645 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
2646 memcpy(s
->prompt
, ssh
->pktin
.body
+ 4, challengelen
);
2647 /* Prompt heuristic comes from OpenSSH */
2648 strncpy(s
->prompt
+ challengelen
,
2649 memchr(s
->prompt
, '\n', challengelen
) ?
2650 "": "\r\nResponse: ",
2651 (sizeof s
->prompt
) - challengelen
);
2652 s
->prompt
[(sizeof s
->prompt
) - 1] = '\0';
2655 if (ssh
->cfg
.try_tis_auth
&&
2656 (s
->supported_auths_mask
& (1 << SSH1_AUTH_CCARD
)) &&
2657 !s
->ccard_auth_refused
) {
2658 s
->pwpkt_type
= SSH1_CMSG_AUTH_CCARD_RESPONSE
;
2659 logevent("Requested CryptoCard authentication");
2660 send_packet(ssh
, SSH1_CMSG_AUTH_CCARD
, PKT_END
);
2662 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_CCARD_CHALLENGE
) {
2663 logevent("CryptoCard authentication declined");
2664 c_write_str(ssh
, "CryptoCard authentication refused.\r\n");
2665 s
->ccard_auth_refused
= 1;
2668 int challengelen
= GET_32BIT(ssh
->pktin
.body
);
2669 logevent("Received CryptoCard challenge");
2670 if (challengelen
> sizeof(s
->prompt
) - 1)
2671 challengelen
= sizeof(s
->prompt
) - 1;/* prevent overrun */
2672 memcpy(s
->prompt
, ssh
->pktin
.body
+ 4, challengelen
);
2673 strncpy(s
->prompt
+ challengelen
,
2674 memchr(s
->prompt
, '\n', challengelen
) ?
2675 "" : "\r\nResponse: ",
2676 sizeof(s
->prompt
) - challengelen
);
2677 s
->prompt
[sizeof(s
->prompt
) - 1] = '\0';
2680 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2681 sprintf(s
->prompt
, "%.90s@%.90s's password: ",
2682 s
->username
, ssh
->savedhost
);
2684 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2685 char *comment
= NULL
;
2688 if (flags
& FLAG_VERBOSE
)
2689 c_write_str(ssh
, "Trying public key authentication.\r\n");
2690 logeventf(ssh
, "Trying public key \"%s\"",
2691 filename_to_str(&ssh
->cfg
.keyfile
));
2692 type
= key_type(&ssh
->cfg
.keyfile
);
2693 if (type
!= SSH_KEYTYPE_SSH1
) {
2694 sprintf(msgbuf
, "Key is of wrong type (%s)",
2695 key_type_to_str(type
));
2697 c_write_str(ssh
, msgbuf
);
2698 c_write_str(ssh
, "\r\n");
2699 s
->tried_publickey
= 1;
2702 if (!rsakey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
2703 if (flags
& FLAG_VERBOSE
)
2704 c_write_str(ssh
, "No passphrase required.\r\n");
2707 sprintf(s
->prompt
, "Passphrase for key \"%.100s\": ", comment
);
2712 * Show password prompt, having first obtained it via a TIS
2713 * or CryptoCard exchange if we're doing TIS or CryptoCard
2717 if (!ssh_get_line(s
->prompt
, s
->password
,
2718 sizeof(s
->password
), TRUE
)) {
2720 * get_line failed to get a password (for example
2721 * because one was supplied on the command line
2722 * which has already failed to work). Terminate.
2724 send_packet(ssh
, SSH1_MSG_DISCONNECT
,
2725 PKT_STR
, "No more passwords available to try",
2727 logevent("Unable to authenticate");
2728 connection_fatal(ssh
->frontend
, "Unable to authenticate");
2729 ssh
->state
= SSH_STATE_CLOSED
;
2733 /* Prompt may have come from server. We've munged it a bit, so
2734 * we know it to be zero-terminated at least once. */
2735 int ret
; /* need not be saved over crReturn */
2736 c_write_untrusted(ssh
, s
->prompt
, strlen(s
->prompt
));
2739 setup_userpass_input(ssh
, s
->password
, sizeof(s
->password
), 0);
2741 crWaitUntil(!ispkt
);
2742 ret
= process_userpass_input(ssh
, in
, inlen
);
2746 c_write_str(ssh
, "\r\n");
2750 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_RSA
) {
2752 * Try public key authentication with the specified
2755 s
->tried_publickey
= 1;
2758 int ret
= loadrsakey(&ssh
->cfg
.keyfile
, &s
->key
, s
->password
);
2760 c_write_str(ssh
, "Couldn't load private key from ");
2761 c_write_str(ssh
, filename_to_str(&ssh
->cfg
.keyfile
));
2762 c_write_str(ssh
, ".\r\n");
2763 continue; /* go and try password */
2766 c_write_str(ssh
, "Wrong passphrase.\r\n");
2767 s
->tried_publickey
= 0;
2768 continue; /* try again */
2773 * Send a public key attempt.
2775 send_packet(ssh
, SSH1_CMSG_AUTH_RSA
,
2776 PKT_BIGNUM
, s
->key
.modulus
, PKT_END
);
2779 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2780 c_write_str(ssh
, "Server refused our public key.\r\n");
2781 continue; /* go and try password */
2783 if (ssh
->pktin
.type
!= SSH1_SMSG_AUTH_RSA_CHALLENGE
) {
2784 bombout((ssh
,"Bizarre response to offer of public key"));
2790 unsigned char buffer
[32];
2791 Bignum challenge
, response
;
2793 ssh1_read_bignum(ssh
->pktin
.body
, &challenge
);
2794 response
= rsadecrypt(challenge
, &s
->key
);
2795 freebn(s
->key
.private_exponent
);/* burn the evidence */
2797 for (i
= 0; i
< 32; i
++) {
2798 buffer
[i
] = bignum_byte(response
, 31 - i
);
2802 MD5Update(&md5c
, buffer
, 32);
2803 MD5Update(&md5c
, s
->session_id
, 16);
2804 MD5Final(buffer
, &md5c
);
2806 send_packet(ssh
, SSH1_CMSG_AUTH_RSA_RESPONSE
,
2807 PKT_DATA
, buffer
, 16, PKT_END
);
2814 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2815 if (flags
& FLAG_VERBOSE
)
2816 c_write_str(ssh
, "Failed to authenticate with"
2817 " our public key.\r\n");
2818 continue; /* go and try password */
2819 } else if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2820 bombout((ssh
,"Bizarre response to RSA authentication response"));
2824 break; /* we're through! */
2826 if (s
->pwpkt_type
== SSH1_CMSG_AUTH_PASSWORD
) {
2828 * Defence against traffic analysis: we send a
2829 * whole bunch of packets containing strings of
2830 * different lengths. One of these strings is the
2831 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2832 * The others are all random data in
2833 * SSH1_MSG_IGNORE packets. This way a passive
2834 * listener can't tell which is the password, and
2835 * hence can't deduce the password length.
2837 * Anybody with a password length greater than 16
2838 * bytes is going to have enough entropy in their
2839 * password that a listener won't find it _that_
2840 * much help to know how long it is. So what we'll
2843 * - if password length < 16, we send 15 packets
2844 * containing string lengths 1 through 15
2846 * - otherwise, we let N be the nearest multiple
2847 * of 8 below the password length, and send 8
2848 * packets containing string lengths N through
2849 * N+7. This won't obscure the order of
2850 * magnitude of the password length, but it will
2851 * introduce a bit of extra uncertainty.
2853 * A few servers (the old 1.2.18 through 1.2.22)
2854 * can't deal with SSH1_MSG_IGNORE. For these
2855 * servers, we need an alternative defence. We make
2856 * use of the fact that the password is interpreted
2857 * as a C string: so we can append a NUL, then some
2860 * One server (a Cisco one) can deal with neither
2861 * SSH1_MSG_IGNORE _nor_ a padded password string.
2862 * For this server we are left with no defences
2863 * against password length sniffing.
2865 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
)) {
2867 * The server can deal with SSH1_MSG_IGNORE, so
2868 * we can use the primary defence.
2870 int bottom
, top
, pwlen
, i
;
2873 pwlen
= strlen(s
->password
);
2875 bottom
= 0; /* zero length passwords are OK! :-) */
2878 bottom
= pwlen
& ~7;
2882 assert(pwlen
>= bottom
&& pwlen
<= top
);
2884 randomstr
= smalloc(top
+ 1);
2886 for (i
= bottom
; i
<= top
; i
++) {
2888 defer_packet(ssh
, s
->pwpkt_type
,
2889 PKT_STR
, s
->password
, PKT_END
);
2891 for (j
= 0; j
< i
; j
++) {
2893 randomstr
[j
] = random_byte();
2894 } while (randomstr
[j
] == '\0');
2896 randomstr
[i
] = '\0';
2897 defer_packet(ssh
, SSH1_MSG_IGNORE
,
2898 PKT_STR
, randomstr
, PKT_END
);
2901 logevent("Sending password with camouflage packets");
2902 ssh_pkt_defersend(ssh
);
2904 else if (!(ssh
->remote_bugs
& BUG_NEEDS_SSH1_PLAIN_PASSWORD
)) {
2906 * The server can't deal with SSH1_MSG_IGNORE
2907 * but can deal with padded passwords, so we
2908 * can use the secondary defence.
2914 len
= strlen(s
->password
);
2915 if (len
< sizeof(string
)) {
2917 strcpy(string
, s
->password
);
2918 len
++; /* cover the zero byte */
2919 while (len
< sizeof(string
)) {
2920 string
[len
++] = (char) random_byte();
2925 logevent("Sending length-padded password");
2926 send_packet(ssh
, s
->pwpkt_type
, PKT_INT
, len
,
2927 PKT_DATA
, ss
, len
, PKT_END
);
2930 * The server has _both_
2931 * BUG_CHOKES_ON_SSH1_IGNORE and
2932 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2933 * therefore nothing we can do.
2936 len
= strlen(s
->password
);
2937 logevent("Sending unpadded password");
2938 send_packet(ssh
, s
->pwpkt_type
, PKT_INT
, len
,
2939 PKT_DATA
, s
->password
, len
, PKT_END
);
2942 send_packet(ssh
, s
->pwpkt_type
, PKT_STR
, s
->password
, PKT_END
);
2945 logevent("Sent password");
2946 memset(s
->password
, 0, strlen(s
->password
));
2948 if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
2949 if (flags
& FLAG_VERBOSE
)
2950 c_write_str(ssh
, "Access denied\r\n");
2951 logevent("Authentication refused");
2952 } else if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
) {
2953 bombout((ssh
,"Strange packet received, type %d", ssh
->pktin
.type
));
2958 logevent("Authentication successful");
2963 void sshfwd_close(struct ssh_channel
*c
)
2967 if (c
&& !c
->closes
) {
2969 * If the channel's remoteid is -1, we have sent
2970 * CHANNEL_OPEN for this channel, but it hasn't even been
2971 * acknowledged by the server. So we must set a close flag
2972 * on it now, and then when the server acks the channel
2973 * open, we can close it then.
2975 if (((int)c
->remoteid
) != -1) {
2976 if (ssh
->version
== 1) {
2977 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
, PKT_INT
, c
->remoteid
,
2980 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
2981 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
2985 c
->closes
= 1; /* sent MSG_CLOSE */
2986 if (c
->type
== CHAN_X11
) {
2988 logevent("Forwarded X11 connection terminated");
2989 } else if (c
->type
== CHAN_SOCKDATA
||
2990 c
->type
== CHAN_SOCKDATA_DORMANT
) {
2992 logevent("Forwarded port closed");
2997 int sshfwd_write(struct ssh_channel
*c
, char *buf
, int len
)
3001 if (ssh
->version
== 1) {
3002 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3003 PKT_INT
, c
->remoteid
,
3004 PKT_INT
, len
, PKT_DATA
, buf
, len
, PKT_END
);
3006 * In SSH1 we can return 0 here - implying that forwarded
3007 * connections are never individually throttled - because
3008 * the only circumstance that can cause throttling will be
3009 * the whole SSH connection backing up, in which case
3010 * _everything_ will be throttled as a whole.
3014 ssh2_add_channel_data(c
, buf
, len
);
3015 return ssh2_try_send(c
);
3019 void sshfwd_unthrottle(struct ssh_channel
*c
, int bufsize
)
3023 if (ssh
->version
== 1) {
3024 if (c
->v
.v1
.throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
3025 c
->v
.v1
.throttling
= 0;
3026 ssh1_throttle(ssh
, -1);
3029 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
3033 static void ssh1_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
3035 crBegin(ssh
->ssh1_protocol_crstate
);
3039 while (!do_ssh1_login(ssh
, in
, inlen
, ispkt
)) {
3042 if (ssh
->state
== SSH_STATE_CLOSED
)
3045 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
3046 logevent("Requesting agent forwarding");
3047 send_packet(ssh
, SSH1_CMSG_AGENT_REQUEST_FORWARDING
, PKT_END
);
3051 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3052 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3053 bombout((ssh
,"Protocol confusion"));
3055 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3056 logevent("Agent forwarding refused");
3058 logevent("Agent forwarding enabled");
3059 ssh
->agentfwd_enabled
= TRUE
;
3063 if (ssh
->cfg
.x11_forward
) {
3064 char proto
[20], data
[64];
3065 logevent("Requesting X11 forwarding");
3066 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
3067 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
3068 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
3069 if (ssh
->v1_local_protoflags
& SSH1_PROTOFLAG_SCREEN_NUMBER
) {
3070 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3071 PKT_STR
, proto
, PKT_STR
, data
,
3072 PKT_INT
, x11_get_screen_number(ssh
->cfg
.x11_display
),
3075 send_packet(ssh
, SSH1_CMSG_X11_REQUEST_FORWARDING
,
3076 PKT_STR
, proto
, PKT_STR
, data
, PKT_END
);
3081 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3082 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3083 bombout((ssh
,"Protocol confusion"));
3085 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3086 logevent("X11 forwarding refused");
3088 logevent("X11 forwarding enabled");
3089 ssh
->X11_fwd_enabled
= TRUE
;
3096 int sport
,dport
,sserv
,dserv
;
3097 char sports
[256], dports
[256], saddr
[256], host
[256];
3099 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh1
);
3100 /* Add port forwardings. */
3101 ssh
->portfwd_strptr
= ssh
->cfg
.portfwd
;
3102 while (*ssh
->portfwd_strptr
) {
3103 type
= *ssh
->portfwd_strptr
++;
3106 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t') {
3107 if (*ssh
->portfwd_strptr
== ':') {
3109 * We've seen a colon in the middle of the
3110 * source port number. This means that
3111 * everything we've seen until now is the
3112 * source _address_, so we'll move it into
3113 * saddr and start sports from the beginning
3116 ssh
->portfwd_strptr
++;
3118 strcpy(saddr
, sports
);
3121 if (n
< 255) sports
[n
++] = *ssh
->portfwd_strptr
++;
3124 if (*ssh
->portfwd_strptr
== '\t')
3125 ssh
->portfwd_strptr
++;
3127 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':') {
3128 if (n
< 255) host
[n
++] = *ssh
->portfwd_strptr
++;
3131 if (*ssh
->portfwd_strptr
== ':')
3132 ssh
->portfwd_strptr
++;
3134 while (*ssh
->portfwd_strptr
) {
3135 if (n
< 255) dports
[n
++] = *ssh
->portfwd_strptr
++;
3138 ssh
->portfwd_strptr
++;
3139 dport
= atoi(dports
);
3143 dport
= net_service_lookup(dports
);
3145 logeventf(ssh
, "Service lookup failed for"
3146 " destination port \"%s\"", dports
);
3149 sport
= atoi(sports
);
3153 sport
= net_service_lookup(sports
);
3155 logeventf(ssh
, "Service lookup failed for source"
3156 " port \"%s\"", sports
);
3159 if (sport
&& dport
) {
3161 pfd_addforward(host
, dport
, *saddr ? saddr
: NULL
,
3162 sport
, ssh
, &ssh
->cfg
);
3163 logeventf(ssh
, "Local port %.*s%.*s%.*s%.*s%d%.*s"
3164 " forwarding to %s:%.*s%.*s%d%.*s",
3165 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
3166 (int)(*saddr?
1:0), ":",
3167 (int)(sserv ?
strlen(sports
) : 0), sports
,
3168 sserv
, "(", sport
, sserv
, ")",
3170 (int)(dserv ?
strlen(dports
) : 0), dports
,
3171 dserv
, "(", dport
, dserv
, ")");
3173 struct ssh_rportfwd
*pf
;
3174 pf
= smalloc(sizeof(*pf
));
3175 strcpy(pf
->dhost
, host
);
3179 "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
3182 if (add234(ssh
->rportfwds
, pf
) != pf
) {
3184 "Duplicate remote port forwarding to %s:%d",
3188 logeventf(ssh
, "Requesting remote port %.*s%.*s%d%.*s"
3189 " forward to %s:%.*s%.*s%d%.*s",
3190 (int)(sserv ?
strlen(sports
) : 0), sports
,
3191 sserv
, "(", sport
, sserv
, ")",
3193 (int)(dserv ?
strlen(dports
) : 0), dports
,
3194 dserv
, "(", dport
, dserv
, ")");
3195 send_packet(ssh
, SSH1_CMSG_PORT_FORWARD_REQUEST
,
3203 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3204 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3205 bombout((ssh
,"Protocol confusion"));
3207 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3208 c_write_str(ssh
, "Server refused port"
3211 logevent("Remote port forwarding enabled");
3218 if (!ssh
->cfg
.nopty
) {
3219 send_packet(ssh
, SSH1_CMSG_REQUEST_PTY
,
3220 PKT_STR
, ssh
->cfg
.termtype
,
3221 PKT_INT
, ssh
->term_height
,
3222 PKT_INT
, ssh
->term_width
,
3223 PKT_INT
, 0, PKT_INT
, 0, PKT_CHAR
, 0, PKT_END
);
3224 ssh
->state
= SSH_STATE_INTERMED
;
3228 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3229 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3230 bombout((ssh
,"Protocol confusion"));
3232 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3233 c_write_str(ssh
, "Server refused to allocate pty\r\n");
3234 ssh
->editing
= ssh
->echoing
= 1;
3236 logevent("Allocated pty");
3238 ssh
->editing
= ssh
->echoing
= 1;
3241 if (ssh
->cfg
.compression
) {
3242 send_packet(ssh
, SSH1_CMSG_REQUEST_COMPRESSION
, PKT_INT
, 6, PKT_END
);
3246 if (ssh
->pktin
.type
!= SSH1_SMSG_SUCCESS
3247 && ssh
->pktin
.type
!= SSH1_SMSG_FAILURE
) {
3248 bombout((ssh
,"Protocol confusion"));
3250 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3251 c_write_str(ssh
, "Server refused to compress\r\n");
3253 logevent("Started compression");
3254 ssh
->v1_compressing
= TRUE
;
3255 ssh
->cs_comp_ctx
= zlib_compress_init();
3256 logevent("Initialised zlib (RFC1950) compression");
3257 ssh
->sc_comp_ctx
= zlib_decompress_init();
3258 logevent("Initialised zlib (RFC1950) decompression");
3262 * Start the shell or command.
3264 * Special case: if the first-choice command is an SSH2
3265 * subsystem (hence not usable here) and the second choice
3266 * exists, we fall straight back to that.
3269 char *cmd
= ssh
->cfg
.remote_cmd_ptr
;
3271 if (ssh
->cfg
.ssh_subsys
&& ssh
->cfg
.remote_cmd_ptr2
) {
3272 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
3273 ssh
->fallback_cmd
= TRUE
;
3276 send_packet(ssh
, SSH1_CMSG_EXEC_CMD
, PKT_STR
, cmd
, PKT_END
);
3278 send_packet(ssh
, SSH1_CMSG_EXEC_SHELL
, PKT_END
);
3279 logevent("Started session");
3282 ssh
->state
= SSH_STATE_SESSION
;
3283 if (ssh
->size_needed
)
3284 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
3285 if (ssh
->eof_needed
)
3286 ssh_special(ssh
, TS_EOF
);
3289 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
3291 ssh
->channels
= newtree234(ssh_channelcmp
);
3295 if (ssh
->pktin
.type
== SSH1_SMSG_STDOUT_DATA
||
3296 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
) {
3297 long len
= GET_32BIT(ssh
->pktin
.body
);
3299 from_backend(ssh
->frontend
,
3300 ssh
->pktin
.type
== SSH1_SMSG_STDERR_DATA
,
3301 (char *)(ssh
->pktin
.body
) + 4, len
);
3302 if (!ssh
->v1_stdout_throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3303 ssh
->v1_stdout_throttling
= 1;
3304 ssh1_throttle(ssh
, +1);
3306 } else if (ssh
->pktin
.type
== SSH1_MSG_DISCONNECT
) {
3307 ssh
->state
= SSH_STATE_CLOSED
;
3308 logevent("Received disconnect request");
3310 } else if (ssh
->pktin
.type
== SSH1_SMSG_X11_OPEN
) {
3311 /* Remote side is trying to open a channel to talk to our
3312 * X-Server. Give them back a local channel number. */
3313 struct ssh_channel
*c
;
3315 logevent("Received X11 connect request");
3316 /* Refuse if X11 forwarding is disabled. */
3317 if (!ssh
->X11_fwd_enabled
) {
3318 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3319 PKT_INT
, GET_32BIT(ssh
->pktin
.body
), PKT_END
);
3320 logevent("Rejected X11 connect request");
3322 c
= smalloc(sizeof(struct ssh_channel
));
3325 if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
3326 ssh
->x11auth
, NULL
, -1, &ssh
->cfg
) != NULL
) {
3327 logevent("opening X11 forward connection failed");
3329 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3330 PKT_INT
, GET_32BIT(ssh
->pktin
.body
),
3334 ("opening X11 forward connection succeeded");
3335 c
->remoteid
= GET_32BIT(ssh
->pktin
.body
);
3336 c
->localid
= alloc_channel_id(ssh
);
3338 c
->v
.v1
.throttling
= 0;
3339 c
->type
= CHAN_X11
; /* identify channel type */
3340 add234(ssh
->channels
, c
);
3341 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3342 PKT_INT
, c
->remoteid
, PKT_INT
,
3343 c
->localid
, PKT_END
);
3344 logevent("Opened X11 forward channel");
3347 } else if (ssh
->pktin
.type
== SSH1_SMSG_AGENT_OPEN
) {
3348 /* Remote side is trying to open a channel to talk to our
3349 * agent. Give them back a local channel number. */
3350 struct ssh_channel
*c
;
3352 /* Refuse if agent forwarding is disabled. */
3353 if (!ssh
->agentfwd_enabled
) {
3354 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3355 PKT_INT
, GET_32BIT(ssh
->pktin
.body
), PKT_END
);
3357 c
= smalloc(sizeof(struct ssh_channel
));
3359 c
->remoteid
= GET_32BIT(ssh
->pktin
.body
);
3360 c
->localid
= alloc_channel_id(ssh
);
3362 c
->v
.v1
.throttling
= 0;
3363 c
->type
= CHAN_AGENT
; /* identify channel type */
3364 c
->u
.a
.lensofar
= 0;
3365 add234(ssh
->channels
, c
);
3366 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3367 PKT_INT
, c
->remoteid
, PKT_INT
, c
->localid
,
3370 } else if (ssh
->pktin
.type
== SSH1_MSG_PORT_OPEN
) {
3371 /* Remote side is trying to open a channel to talk to a
3372 * forwarded port. Give them back a local channel number. */
3373 struct ssh_channel
*c
;
3374 struct ssh_rportfwd pf
;
3376 char host
[256], buf
[1024];
3378 c
= smalloc(sizeof(struct ssh_channel
));
3381 hostsize
= GET_32BIT(ssh
->pktin
.body
+4);
3382 for (h
= host
, p
= (char *)(ssh
->pktin
.body
+8);
3383 hostsize
!= 0; hostsize
--) {
3384 if (h
+1 < host
+sizeof(host
))
3389 port
= GET_32BIT(p
);
3391 strcpy(pf
.dhost
, host
);
3394 if (find234(ssh
->rportfwds
, &pf
, NULL
) == NULL
) {
3395 sprintf(buf
, "Rejected remote port open request for %s:%d",
3398 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3399 PKT_INT
, GET_32BIT(ssh
->pktin
.body
), PKT_END
);
3401 sprintf(buf
, "Received remote port open request for %s:%d",
3404 e
= pfd_newconnect(&c
->u
.pfd
.s
, host
, port
, c
, &ssh
->cfg
);
3407 sprintf(buf
, "Port open failed: %s", e
);
3410 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_FAILURE
,
3411 PKT_INT
, GET_32BIT(ssh
->pktin
.body
),
3414 c
->remoteid
= GET_32BIT(ssh
->pktin
.body
);
3415 c
->localid
= alloc_channel_id(ssh
);
3417 c
->v
.v1
.throttling
= 0;
3418 c
->type
= CHAN_SOCKDATA
; /* identify channel type */
3419 add234(ssh
->channels
, c
);
3420 send_packet(ssh
, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
,
3421 PKT_INT
, c
->remoteid
, PKT_INT
,
3422 c
->localid
, PKT_END
);
3423 logevent("Forwarded port opened successfully");
3427 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_OPEN_CONFIRMATION
) {
3428 unsigned int remoteid
= GET_32BIT(ssh
->pktin
.body
);
3429 unsigned int localid
= GET_32BIT(ssh
->pktin
.body
+4);
3430 struct ssh_channel
*c
;
3432 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3433 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3434 c
->remoteid
= localid
;
3435 c
->type
= CHAN_SOCKDATA
;
3436 c
->v
.v1
.throttling
= 0;
3437 pfd_confirm(c
->u
.pfd
.s
);
3440 if (c
&& c
->closes
) {
3442 * We have a pending close on this channel,
3443 * which we decided on before the server acked
3444 * the channel open. So now we know the
3445 * remoteid, we can close it again.
3447 send_packet(ssh
, SSH1_MSG_CHANNEL_CLOSE
,
3448 PKT_INT
, c
->remoteid
, PKT_END
);
3451 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_OPEN_FAILURE
) {
3452 unsigned int remoteid
= GET_32BIT(ssh
->pktin
.body
);
3453 struct ssh_channel
*c
;
3455 c
= find234(ssh
->channels
, &remoteid
, ssh_channelfind
);
3456 if (c
&& c
->type
== CHAN_SOCKDATA_DORMANT
) {
3457 logevent("Forwarded connection refused by server");
3458 pfd_close(c
->u
.pfd
.s
);
3459 del234(ssh
->channels
, c
);
3463 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE
||
3464 ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION
) {
3465 /* Remote side closes a channel. */
3466 unsigned i
= GET_32BIT(ssh
->pktin
.body
);
3467 struct ssh_channel
*c
;
3468 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3469 if (c
&& ((int)c
->remoteid
) != -1) {
3472 (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
1 : 2);
3474 if ((c
->closes
== 0) && (c
->type
== CHAN_X11
)) {
3475 logevent("Forwarded X11 connection terminated");
3476 assert(c
->u
.x11
.s
!= NULL
);
3477 x11_close(c
->u
.x11
.s
);
3480 if ((c
->closes
== 0) && (c
->type
== CHAN_SOCKDATA
)) {
3481 logevent("Forwarded port closed");
3482 assert(c
->u
.pfd
.s
!= NULL
);
3483 pfd_close(c
->u
.pfd
.s
);
3487 c
->closes
|= (closetype
<< 2); /* seen this message */
3488 if (!(c
->closes
& closetype
)) {
3489 send_packet(ssh
, ssh
->pktin
.type
, PKT_INT
, c
->remoteid
,
3491 c
->closes
|= closetype
; /* sent it too */
3494 if (c
->closes
== 15) {
3495 del234(ssh
->channels
, c
);
3499 bombout((ssh
,"Received CHANNEL_CLOSE%s for %s channel %d\n",
3500 ssh
->pktin
.type
== SSH1_MSG_CHANNEL_CLOSE ?
"" :
3501 "_CONFIRMATION", c ?
"half-open" : "nonexistent",
3504 } else if (ssh
->pktin
.type
== SSH1_MSG_CHANNEL_DATA
) {
3505 /* Data sent down one of our channels. */
3506 int i
= GET_32BIT(ssh
->pktin
.body
);
3507 int len
= GET_32BIT(ssh
->pktin
.body
+ 4);
3508 unsigned char *p
= ssh
->pktin
.body
+ 8;
3509 struct ssh_channel
*c
;
3510 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
3515 bufsize
= x11_send(c
->u
.x11
.s
, (char *)p
, len
);
3518 bufsize
= pfd_send(c
->u
.pfd
.s
, (char *)p
, len
);
3521 /* Data for an agent message. Buffer it. */
3523 if (c
->u
.a
.lensofar
< 4) {
3524 int l
= min(4 - c
->u
.a
.lensofar
, len
);
3525 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
, p
,
3529 c
->u
.a
.lensofar
+= l
;
3531 if (c
->u
.a
.lensofar
== 4) {
3533 4 + GET_32BIT(c
->u
.a
.msglen
);
3534 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
3535 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
3537 if (c
->u
.a
.lensofar
>= 4 && len
> 0) {
3539 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
3541 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
, p
,
3545 c
->u
.a
.lensofar
+= l
;
3547 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
3548 void *reply
, *sentreply
;
3550 agent_query(c
->u
.a
.message
,
3551 c
->u
.a
.totallen
, &reply
,
3556 /* Fake SSH_AGENT_FAILURE. */
3557 sentreply
= "\0\0\0\1\5";
3560 send_packet(ssh
, SSH1_MSG_CHANNEL_DATA
,
3561 PKT_INT
, c
->remoteid
,
3563 PKT_DATA
, sentreply
, replylen
,
3567 sfree(c
->u
.a
.message
);
3568 c
->u
.a
.lensofar
= 0;
3571 bufsize
= 0; /* agent channels never back up */
3574 if (!c
->v
.v1
.throttling
&& bufsize
> SSH1_BUFFER_LIMIT
) {
3575 c
->v
.v1
.throttling
= 1;
3576 ssh1_throttle(ssh
, +1);
3579 } else if (ssh
->pktin
.type
== SSH1_SMSG_SUCCESS
) {
3580 /* may be from EXEC_SHELL on some servers */
3581 } else if (ssh
->pktin
.type
== SSH1_SMSG_FAILURE
) {
3582 /* may be from EXEC_SHELL on some servers
3583 * if no pty is available or in other odd cases. Ignore */
3584 } else if (ssh
->pktin
.type
== SSH1_SMSG_EXIT_STATUS
) {
3586 ssh
->exitcode
= GET_32BIT(ssh
->pktin
.body
);
3587 sprintf(buf
, "Server sent command exit status %d",
3590 send_packet(ssh
, SSH1_CMSG_EXIT_CONFIRMATION
, PKT_END
);
3592 * In case `helpful' firewalls or proxies tack
3593 * extra human-readable text on the end of the
3594 * session which we might mistake for another
3595 * encrypted packet, we close the session once
3596 * we've sent EXIT_CONFIRMATION.
3598 ssh
->state
= SSH_STATE_CLOSED
;
3601 bombout((ssh
,"Strange packet received: type %d", ssh
->pktin
.type
));
3606 int len
= min(inlen
, 512);
3607 send_packet(ssh
, SSH1_CMSG_STDIN_DATA
,
3608 PKT_INT
, len
, PKT_DATA
, in
, len
, PKT_END
);
3619 * Utility routine for decoding comma-separated strings in KEXINIT.
3621 static int in_commasep_string(char *needle
, char *haystack
, int haylen
)
3624 if (!needle
|| !haystack
) /* protect against null pointers */
3626 needlen
= strlen(needle
);
3629 * Is it at the start of the string?
3631 if (haylen
>= needlen
&& /* haystack is long enough */
3632 !memcmp(needle
, haystack
, needlen
) && /* initial match */
3633 (haylen
== needlen
|| haystack
[needlen
] == ',')
3634 /* either , or EOS follows */
3638 * If not, search for the next comma and resume after that.
3639 * If no comma found, terminate.
3641 while (haylen
> 0 && *haystack
!= ',')
3642 haylen
--, haystack
++;
3645 haylen
--, haystack
++; /* skip over comma itself */
3650 * SSH2 key creation method.
3652 static void ssh2_mkkey(Ssh ssh
, Bignum K
, unsigned char *H
,
3653 unsigned char *sessid
, char chr
,
3654 unsigned char *keyspace
)
3657 /* First 20 bytes. */
3659 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
3661 SHA_Bytes(&s
, H
, 20);
3662 SHA_Bytes(&s
, &chr
, 1);
3663 SHA_Bytes(&s
, sessid
, 20);
3664 SHA_Final(&s
, keyspace
);
3665 /* Next 20 bytes. */
3667 if (!(ssh
->remote_bugs
& BUG_SSH2_DERIVEKEY
))
3669 SHA_Bytes(&s
, H
, 20);
3670 SHA_Bytes(&s
, keyspace
, 20);
3671 SHA_Final(&s
, keyspace
+ 20);
3675 * Handle the SSH2 transport layer.
3677 static int do_ssh2_transport(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
3679 struct do_ssh2_transport_state
{
3680 int nbits
, pbits
, warn
;
3681 Bignum p
, g
, e
, f
, K
;
3682 int kex_init_value
, kex_reply_value
;
3683 const struct ssh_mac
**maclist
;
3685 const struct ssh2_cipher
*cscipher_tobe
;
3686 const struct ssh2_cipher
*sccipher_tobe
;
3687 const struct ssh_mac
*csmac_tobe
;
3688 const struct ssh_mac
*scmac_tobe
;
3689 const struct ssh_compress
*cscomp_tobe
;
3690 const struct ssh_compress
*sccomp_tobe
;
3691 char *hostkeydata
, *sigdata
, *keystr
, *fingerprint
;
3692 int hostkeylen
, siglen
;
3693 void *hkey
; /* actual host key */
3694 unsigned char exchange_hash
[20];
3695 int n_preferred_ciphers
;
3696 const struct ssh2_ciphers
*preferred_ciphers
[CIPHER_MAX
];
3697 const struct ssh_compress
*preferred_comp
;
3700 crState(do_ssh2_transport_state
);
3702 crBegin(ssh
->do_ssh2_transport_crstate
);
3704 s
->cscipher_tobe
= s
->sccipher_tobe
= NULL
;
3705 s
->csmac_tobe
= s
->scmac_tobe
= NULL
;
3706 s
->cscomp_tobe
= s
->sccomp_tobe
= NULL
;
3714 * Set up the preferred ciphers. (NULL => warn below here)
3716 s
->n_preferred_ciphers
= 0;
3717 for (i
= 0; i
< CIPHER_MAX
; i
++) {
3718 switch (ssh
->cfg
.ssh_cipherlist
[i
]) {
3719 case CIPHER_BLOWFISH
:
3720 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_blowfish
;
3723 if (ssh
->cfg
.ssh2_des_cbc
) {
3724 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_des
;
3728 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_3des
;
3731 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = &ssh2_aes
;
3734 /* Flag for later. Don't bother if it's the last in
3736 if (i
< CIPHER_MAX
- 1) {
3737 s
->preferred_ciphers
[s
->n_preferred_ciphers
++] = NULL
;
3745 * Set up preferred compression.
3747 if (ssh
->cfg
.compression
)
3748 s
->preferred_comp
= &ssh_zlib
;
3750 s
->preferred_comp
= &ssh_comp_none
;
3753 * Be prepared to work around the buggy MAC problem.
3755 if (ssh
->remote_bugs
& BUG_SSH2_HMAC
)
3756 s
->maclist
= buggymacs
, s
->nmacs
= lenof(buggymacs
);
3758 s
->maclist
= macs
, s
->nmacs
= lenof(macs
);
3762 int i
, j
, cipherstr_started
;
3765 * Construct and send our key exchange packet.
3767 ssh2_pkt_init(ssh
, SSH2_MSG_KEXINIT
);
3768 for (i
= 0; i
< 16; i
++)
3769 ssh2_pkt_addbyte(ssh
, (unsigned char) random_byte());
3770 /* List key exchange algorithms. */
3771 ssh2_pkt_addstring_start(ssh
);
3772 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3773 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
3774 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
3776 ssh2_pkt_addstring_str(ssh
, kex_algs
[i
]->name
);
3777 if (i
< lenof(kex_algs
) - 1)
3778 ssh2_pkt_addstring_str(ssh
, ",");
3780 /* List server host key algorithms. */
3781 ssh2_pkt_addstring_start(ssh
);
3782 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3783 ssh2_pkt_addstring_str(ssh
, hostkey_algs
[i
]->name
);
3784 if (i
< lenof(hostkey_algs
) - 1)
3785 ssh2_pkt_addstring_str(ssh
, ",");
3787 /* List client->server encryption algorithms. */
3788 ssh2_pkt_addstring_start(ssh
);
3789 cipherstr_started
= 0;
3790 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
3791 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
3792 if (!c
) continue; /* warning flag */
3793 for (j
= 0; j
< c
->nciphers
; j
++) {
3794 if (cipherstr_started
)
3795 ssh2_pkt_addstring_str(ssh
, ",");
3796 ssh2_pkt_addstring_str(ssh
, c
->list
[j
]->name
);
3797 cipherstr_started
= 1;
3800 /* List server->client encryption algorithms. */
3801 ssh2_pkt_addstring_start(ssh
);
3802 cipherstr_started
= 0;
3803 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
3804 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
3805 if (!c
) continue; /* warning flag */
3806 for (j
= 0; j
< c
->nciphers
; j
++) {
3807 if (cipherstr_started
)
3808 ssh2_pkt_addstring_str(ssh
, ",");
3809 ssh2_pkt_addstring_str(ssh
, c
->list
[j
]->name
);
3810 cipherstr_started
= 1;
3813 /* List client->server MAC algorithms. */
3814 ssh2_pkt_addstring_start(ssh
);
3815 for (i
= 0; i
< s
->nmacs
; i
++) {
3816 ssh2_pkt_addstring_str(ssh
, s
->maclist
[i
]->name
);
3817 if (i
< s
->nmacs
- 1)
3818 ssh2_pkt_addstring_str(ssh
, ",");
3820 /* List server->client MAC algorithms. */
3821 ssh2_pkt_addstring_start(ssh
);
3822 for (i
= 0; i
< s
->nmacs
; i
++) {
3823 ssh2_pkt_addstring_str(ssh
, s
->maclist
[i
]->name
);
3824 if (i
< s
->nmacs
- 1)
3825 ssh2_pkt_addstring_str(ssh
, ",");
3827 /* List client->server compression algorithms. */
3828 ssh2_pkt_addstring_start(ssh
);
3829 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3830 const struct ssh_compress
*c
=
3831 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
3832 ssh2_pkt_addstring_str(ssh
, c
->name
);
3833 if (i
< lenof(compressions
))
3834 ssh2_pkt_addstring_str(ssh
, ",");
3836 /* List server->client compression algorithms. */
3837 ssh2_pkt_addstring_start(ssh
);
3838 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3839 const struct ssh_compress
*c
=
3840 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
3841 ssh2_pkt_addstring_str(ssh
, c
->name
);
3842 if (i
< lenof(compressions
))
3843 ssh2_pkt_addstring_str(ssh
, ",");
3845 /* List client->server languages. Empty list. */
3846 ssh2_pkt_addstring_start(ssh
);
3847 /* List server->client languages. Empty list. */
3848 ssh2_pkt_addstring_start(ssh
);
3849 /* First KEX packet does _not_ follow, because we're not that brave. */
3850 ssh2_pkt_addbool(ssh
, FALSE
);
3852 ssh2_pkt_adduint32(ssh
, 0);
3855 ssh
->exhash
= ssh
->exhashbase
;
3856 sha_string(&ssh
->exhash
, ssh
->pktout
.data
+ 5, ssh
->pktout
.length
- 5);
3862 if (ssh
->pktin
.length
> 5)
3863 sha_string(&ssh
->exhash
, ssh
->pktin
.data
+ 5, ssh
->pktin
.length
- 5);
3866 * Now examine the other side's KEXINIT to see what we're up
3873 if (ssh
->pktin
.type
!= SSH2_MSG_KEXINIT
) {
3874 bombout((ssh
,"expected key exchange packet from server"));
3878 ssh
->hostkey
= NULL
;
3879 s
->cscipher_tobe
= NULL
;
3880 s
->sccipher_tobe
= NULL
;
3881 s
->csmac_tobe
= NULL
;
3882 s
->scmac_tobe
= NULL
;
3883 s
->cscomp_tobe
= NULL
;
3884 s
->sccomp_tobe
= NULL
;
3885 ssh
->pktin
.savedpos
+= 16; /* skip garbage cookie */
3886 ssh2_pkt_getstring(ssh
, &str
, &len
); /* key exchange algorithms */
3887 for (i
= 0; i
< lenof(kex_algs
); i
++) {
3888 if (kex_algs
[i
] == &ssh_diffiehellman_gex
&&
3889 (ssh
->remote_bugs
& BUG_SSH2_DH_GEX
))
3891 if (in_commasep_string(kex_algs
[i
]->name
, str
, len
)) {
3892 ssh
->kex
= kex_algs
[i
];
3896 ssh2_pkt_getstring(ssh
, &str
, &len
); /* host key algorithms */
3897 for (i
= 0; i
< lenof(hostkey_algs
); i
++) {
3898 if (in_commasep_string(hostkey_algs
[i
]->name
, str
, len
)) {
3899 ssh
->hostkey
= hostkey_algs
[i
];
3903 ssh2_pkt_getstring(ssh
, &str
, &len
); /* client->server cipher */
3905 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
3906 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
3910 for (j
= 0; j
< c
->nciphers
; j
++) {
3911 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3912 s
->cscipher_tobe
= c
->list
[j
];
3917 if (s
->cscipher_tobe
) {
3919 askcipher(ssh
->frontend
, s
->cscipher_tobe
->name
, 1);
3923 if (!s
->cscipher_tobe
) {
3924 bombout((ssh
,"Couldn't agree a client-to-server cipher (available: %s)",
3925 str ? str
: "(null)"));
3929 ssh2_pkt_getstring(ssh
, &str
, &len
); /* server->client cipher */
3931 for (i
= 0; i
< s
->n_preferred_ciphers
; i
++) {
3932 const struct ssh2_ciphers
*c
= s
->preferred_ciphers
[i
];
3936 for (j
= 0; j
< c
->nciphers
; j
++) {
3937 if (in_commasep_string(c
->list
[j
]->name
, str
, len
)) {
3938 s
->sccipher_tobe
= c
->list
[j
];
3943 if (s
->sccipher_tobe
) {
3945 askcipher(ssh
->frontend
, s
->sccipher_tobe
->name
, 2);
3949 if (!s
->sccipher_tobe
) {
3950 bombout((ssh
,"Couldn't agree a server-to-client cipher (available: %s)",
3951 str ? str
: "(null)"));
3955 ssh2_pkt_getstring(ssh
, &str
, &len
); /* client->server mac */
3956 for (i
= 0; i
< s
->nmacs
; i
++) {
3957 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
3958 s
->csmac_tobe
= s
->maclist
[i
];
3962 ssh2_pkt_getstring(ssh
, &str
, &len
); /* server->client mac */
3963 for (i
= 0; i
< s
->nmacs
; i
++) {
3964 if (in_commasep_string(s
->maclist
[i
]->name
, str
, len
)) {
3965 s
->scmac_tobe
= s
->maclist
[i
];
3969 ssh2_pkt_getstring(ssh
, &str
, &len
); /* client->server compression */
3970 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3971 const struct ssh_compress
*c
=
3972 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
3973 if (in_commasep_string(c
->name
, str
, len
)) {
3978 ssh2_pkt_getstring(ssh
, &str
, &len
); /* server->client compression */
3979 for (i
= 0; i
< lenof(compressions
) + 1; i
++) {
3980 const struct ssh_compress
*c
=
3981 i
== 0 ? s
->preferred_comp
: compressions
[i
- 1];
3982 if (in_commasep_string(c
->name
, str
, len
)) {
3990 * Work out the number of bits of key we will need from the key
3991 * exchange. We start with the maximum key length of either
3997 csbits
= s
->cscipher_tobe
->keylen
;
3998 scbits
= s
->sccipher_tobe
->keylen
;
3999 s
->nbits
= (csbits
> scbits ? csbits
: scbits
);
4001 /* The keys only have 160-bit entropy, since they're based on
4002 * a SHA-1 hash. So cap the key size at 160 bits. */
4007 * If we're doing Diffie-Hellman group exchange, start by
4008 * requesting a group.
4010 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4011 logevent("Doing Diffie-Hellman group exchange");
4012 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGEX
;
4014 * Work out how big a DH group we will need to allow that
4017 s
->pbits
= 512 << ((s
->nbits
- 1) / 64);
4018 ssh2_pkt_init(ssh
, SSH2_MSG_KEX_DH_GEX_REQUEST
);
4019 ssh2_pkt_adduint32(ssh
, s
->pbits
);
4023 if (ssh
->pktin
.type
!= SSH2_MSG_KEX_DH_GEX_GROUP
) {
4024 bombout((ssh
,"expected key exchange group packet from server"));
4027 s
->p
= ssh2_pkt_getmp(ssh
);
4028 s
->g
= ssh2_pkt_getmp(ssh
);
4029 ssh
->kex_ctx
= dh_setup_group(s
->p
, s
->g
);
4030 s
->kex_init_value
= SSH2_MSG_KEX_DH_GEX_INIT
;
4031 s
->kex_reply_value
= SSH2_MSG_KEX_DH_GEX_REPLY
;
4033 ssh
->pkt_ctx
|= SSH2_PKTCTX_DHGROUP1
;
4034 ssh
->kex_ctx
= dh_setup_group1();
4035 s
->kex_init_value
= SSH2_MSG_KEXDH_INIT
;
4036 s
->kex_reply_value
= SSH2_MSG_KEXDH_REPLY
;
4039 logevent("Doing Diffie-Hellman key exchange");
4041 * Now generate and send e for Diffie-Hellman.
4043 s
->e
= dh_create_e(ssh
->kex_ctx
, s
->nbits
* 2);
4044 ssh2_pkt_init(ssh
, s
->kex_init_value
);
4045 ssh2_pkt_addmp(ssh
, s
->e
);
4049 if (ssh
->pktin
.type
!= s
->kex_reply_value
) {
4050 bombout((ssh
,"expected key exchange reply packet from server"));
4053 ssh2_pkt_getstring(ssh
, &s
->hostkeydata
, &s
->hostkeylen
);
4054 s
->f
= ssh2_pkt_getmp(ssh
);
4055 ssh2_pkt_getstring(ssh
, &s
->sigdata
, &s
->siglen
);
4057 s
->K
= dh_find_K(ssh
->kex_ctx
, s
->f
);
4059 sha_string(&ssh
->exhash
, s
->hostkeydata
, s
->hostkeylen
);
4060 if (ssh
->kex
== &ssh_diffiehellman_gex
) {
4061 sha_uint32(&ssh
->exhash
, s
->pbits
);
4062 sha_mpint(&ssh
->exhash
, s
->p
);
4063 sha_mpint(&ssh
->exhash
, s
->g
);
4065 sha_mpint(&ssh
->exhash
, s
->e
);
4066 sha_mpint(&ssh
->exhash
, s
->f
);
4067 sha_mpint(&ssh
->exhash
, s
->K
);
4068 SHA_Final(&ssh
->exhash
, s
->exchange_hash
);
4070 dh_cleanup(ssh
->kex_ctx
);
4071 ssh
->kex_ctx
= NULL
;
4074 debug(("Exchange hash is:\n"));
4075 dmemdump(s
->exchange_hash
, 20);
4078 s
->hkey
= ssh
->hostkey
->newkey(s
->hostkeydata
, s
->hostkeylen
);
4080 !ssh
->hostkey
->verifysig(s
->hkey
, s
->sigdata
, s
->siglen
,
4081 (char *)s
->exchange_hash
, 20)) {
4082 bombout((ssh
,"Server's host key did not match the signature supplied"));
4087 * Authenticate remote host: verify host key. (We've already
4088 * checked the signature of the exchange hash.)
4090 s
->keystr
= ssh
->hostkey
->fmtkey(s
->hkey
);
4091 s
->fingerprint
= ssh
->hostkey
->fingerprint(s
->hkey
);
4092 verify_ssh_host_key(ssh
->frontend
,
4093 ssh
->savedhost
, ssh
->savedport
, ssh
->hostkey
->keytype
,
4094 s
->keystr
, s
->fingerprint
);
4095 if (s
->first_kex
) { /* don't bother logging this in rekeys */
4096 logevent("Host key fingerprint is:");
4097 logevent(s
->fingerprint
);
4099 sfree(s
->fingerprint
);
4101 ssh
->hostkey
->freekey(s
->hkey
);
4104 * Send SSH2_MSG_NEWKEYS.
4106 ssh2_pkt_init(ssh
, SSH2_MSG_NEWKEYS
);
4110 * Expect SSH2_MSG_NEWKEYS from server.
4113 if (ssh
->pktin
.type
!= SSH2_MSG_NEWKEYS
) {
4114 bombout((ssh
,"expected new-keys packet from server"));
4119 * Create and initialise session keys.
4121 if (ssh
->cs_cipher_ctx
)
4122 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
4123 ssh
->cscipher
= s
->cscipher_tobe
;
4124 ssh
->cs_cipher_ctx
= ssh
->cscipher
->make_context();
4126 if (ssh
->sc_cipher_ctx
)
4127 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
4128 ssh
->sccipher
= s
->sccipher_tobe
;
4129 ssh
->sc_cipher_ctx
= ssh
->sccipher
->make_context();
4131 if (ssh
->cs_mac_ctx
)
4132 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
4133 ssh
->csmac
= s
->csmac_tobe
;
4134 ssh
->cs_mac_ctx
= ssh
->csmac
->make_context();
4136 if (ssh
->sc_mac_ctx
)
4137 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
4138 ssh
->scmac
= s
->scmac_tobe
;
4139 ssh
->sc_mac_ctx
= ssh
->scmac
->make_context();
4141 if (ssh
->cs_comp_ctx
)
4142 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
4143 ssh
->cscomp
= s
->cscomp_tobe
;
4144 ssh
->cs_comp_ctx
= ssh
->cscomp
->compress_init();
4146 if (ssh
->sc_comp_ctx
)
4147 ssh
->sccomp
->decompress_cleanup(ssh
->sc_comp_ctx
);
4148 ssh
->sccomp
= s
->sccomp_tobe
;
4149 ssh
->sc_comp_ctx
= ssh
->sccomp
->decompress_init();
4152 * Set IVs after keys. Here we use the exchange hash from the
4153 * _first_ key exchange.
4156 unsigned char keyspace
[40];
4158 memcpy(ssh
->v2_session_id
, s
->exchange_hash
,
4159 sizeof(s
->exchange_hash
));
4160 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'C',keyspace
);
4161 ssh
->cscipher
->setkey(ssh
->cs_cipher_ctx
, keyspace
);
4162 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'D',keyspace
);
4163 ssh
->sccipher
->setkey(ssh
->sc_cipher_ctx
, keyspace
);
4164 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'A',keyspace
);
4165 ssh
->cscipher
->setiv(ssh
->cs_cipher_ctx
, keyspace
);
4166 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'B',keyspace
);
4167 ssh
->sccipher
->setiv(ssh
->sc_cipher_ctx
, keyspace
);
4168 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'E',keyspace
);
4169 ssh
->csmac
->setkey(ssh
->cs_mac_ctx
, keyspace
);
4170 ssh2_mkkey(ssh
,s
->K
,s
->exchange_hash
,ssh
->v2_session_id
,'F',keyspace
);
4171 ssh
->scmac
->setkey(ssh
->sc_mac_ctx
, keyspace
);
4173 logeventf(ssh
, "Initialised %.200s client->server encryption",
4174 ssh
->cscipher
->text_name
);
4175 logeventf(ssh
, "Initialised %.200s server->client encryption",
4176 ssh
->sccipher
->text_name
);
4177 if (ssh
->cscomp
->text_name
)
4178 logeventf(ssh
, "Initialised %s compression",
4179 ssh
->cscomp
->text_name
);
4180 if (ssh
->sccomp
->text_name
)
4181 logeventf(ssh
, "Initialised %s decompression",
4182 ssh
->sccomp
->text_name
);
4185 * If this is the first key exchange phase, we must pass the
4186 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4187 * wants to see it but because it will need time to initialise
4188 * itself before it sees an actual packet. In subsequent key
4189 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4190 * it would only confuse the layer above.
4192 if (!s
->first_kex
) {
4198 * Now we're encrypting. Begin returning 1 to the protocol main
4199 * function so that other things can run on top of the
4200 * transport. If we ever see a KEXINIT, we must go back to the
4203 while (!(ispkt
&& ssh
->pktin
.type
== SSH2_MSG_KEXINIT
)) {
4206 logevent("Server initiated key re-exchange");
4207 goto begin_key_exchange
;
4213 * Add data to an SSH2 channel output buffer.
4215 static void ssh2_add_channel_data(struct ssh_channel
*c
, char *buf
,
4218 bufchain_add(&c
->v
.v2
.outbuffer
, buf
, len
);
4222 * Attempt to send data on an SSH2 channel.
4224 static int ssh2_try_send(struct ssh_channel
*c
)
4228 while (c
->v
.v2
.remwindow
> 0 && bufchain_size(&c
->v
.v2
.outbuffer
) > 0) {
4231 bufchain_prefix(&c
->v
.v2
.outbuffer
, &data
, &len
);
4232 if ((unsigned)len
> c
->v
.v2
.remwindow
)
4233 len
= c
->v
.v2
.remwindow
;
4234 if ((unsigned)len
> c
->v
.v2
.remmaxpkt
)
4235 len
= c
->v
.v2
.remmaxpkt
;
4236 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_DATA
);
4237 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
4238 ssh2_pkt_addstring_start(ssh
);
4239 ssh2_pkt_addstring_data(ssh
, data
, len
);
4241 bufchain_consume(&c
->v
.v2
.outbuffer
, len
);
4242 c
->v
.v2
.remwindow
-= len
;
4246 * After having sent as much data as we can, return the amount
4249 return bufchain_size(&c
->v
.v2
.outbuffer
);
4253 * Potentially enlarge the window on an SSH2 channel.
4255 static void ssh2_set_window(struct ssh_channel
*c
, unsigned newwin
)
4260 * Never send WINDOW_ADJUST for a channel that the remote side
4261 * already thinks it's closed; there's no point, since it won't
4262 * be sending any more data anyway.
4267 if (newwin
> c
->v
.v2
.locwindow
) {
4268 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
4269 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
4270 ssh2_pkt_adduint32(ssh
, newwin
- c
->v
.v2
.locwindow
);
4272 c
->v
.v2
.locwindow
= newwin
;
4277 * Handle the SSH2 userauth and connection layers.
4279 static void do_ssh2_authconn(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
4281 struct do_ssh2_authconn_state
{
4283 AUTH_INVALID
, AUTH_PUBLICKEY_AGENT
, AUTH_PUBLICKEY_FILE
,
4285 AUTH_KEYBOARD_INTERACTIVE
4289 AUTH_TYPE_PUBLICKEY
,
4290 AUTH_TYPE_PUBLICKEY_OFFER_LOUD
,
4291 AUTH_TYPE_PUBLICKEY_OFFER_QUIET
,
4293 AUTH_TYPE_KEYBOARD_INTERACTIVE
,
4294 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4296 int gotit
, need_pw
, can_pubkey
, can_passwd
, can_keyb_inter
;
4297 int tried_pubkey_config
, tried_agent
, tried_keyb_inter
;
4298 int kbd_inter_running
;
4300 int num_prompts
, curr_prompt
, echo
;
4305 void *publickey_blob
;
4306 int publickey_bloblen
;
4307 unsigned char request
[5], *response
, *p
;
4311 char *pkblob
, *alg
, *commentp
;
4312 int pklen
, alglen
, commentlen
;
4313 int siglen
, retlen
, len
;
4314 char *q
, *agentreq
, *ret
;
4317 crState(do_ssh2_authconn_state
);
4319 crBegin(ssh
->do_ssh2_authconn_crstate
);
4322 * Request userauth protocol, and await a response to it.
4324 ssh2_pkt_init(ssh
, SSH2_MSG_SERVICE_REQUEST
);
4325 ssh2_pkt_addstring(ssh
, "ssh-userauth");
4327 crWaitUntilV(ispkt
);
4328 if (ssh
->pktin
.type
!= SSH2_MSG_SERVICE_ACCEPT
) {
4329 bombout((ssh
,"Server refused user authentication protocol"));
4334 * We repeat this whole loop, including the username prompt,
4335 * until we manage a successful authentication. If the user
4336 * types the wrong _password_, they can be sent back to the
4337 * beginning to try another username, if this is configured on.
4338 * (If they specify a username in the config, they are never
4339 * asked, even if they do give a wrong password.)
4341 * I think this best serves the needs of
4343 * - the people who have no configuration, no keys, and just
4344 * want to try repeated (username,password) pairs until they
4345 * type both correctly
4347 * - people who have keys and configuration but occasionally
4348 * need to fall back to passwords
4350 * - people with a key held in Pageant, who might not have
4351 * logged in to a particular machine before; so they want to
4352 * type a username, and then _either_ their key will be
4353 * accepted, _or_ they will type a password. If they mistype
4354 * the username they will want to be able to get back and
4357 s
->username
[0] = '\0';
4358 s
->got_username
= FALSE
;
4363 if (s
->got_username
&& !ssh
->cfg
.change_username
) {
4365 * We got a username last time round this loop, and
4366 * with change_username turned off we don't try to get
4369 } else if ((flags
& FLAG_INTERACTIVE
) && !*ssh
->cfg
.username
) {
4370 if (ssh_get_line
&& !ssh_getline_pw_only
) {
4371 if (!ssh_get_line("login as: ",
4372 s
->username
, sizeof(s
->username
), FALSE
)) {
4374 * get_line failed to get a username.
4377 logevent("No username provided. Abandoning session.");
4378 ssh
->state
= SSH_STATE_CLOSED
;
4382 int ret
; /* need not be saved across crReturn */
4383 c_write_str(ssh
, "login as: ");
4385 setup_userpass_input(ssh
, s
->username
, sizeof(s
->username
), 1);
4387 crWaitUntilV(!ispkt
);
4388 ret
= process_userpass_input(ssh
, in
, inlen
);
4392 c_write_str(ssh
, "\r\n");
4394 s
->username
[strcspn(s
->username
, "\n\r")] = '\0';
4397 strncpy(s
->username
, ssh
->cfg
.username
, sizeof(s
->username
));
4398 s
->username
[sizeof(s
->username
)-1] = '\0';
4399 if ((flags
& FLAG_VERBOSE
) || (flags
& FLAG_INTERACTIVE
)) {
4400 stuff
= dupprintf("Using username \"%s\".\r\n", s
->username
);
4401 c_write_str(ssh
, stuff
);
4405 s
->got_username
= TRUE
;
4408 * Send an authentication request using method "none": (a)
4409 * just in case it succeeds, and (b) so that we know what
4410 * authentication methods we can usefully try next.
4412 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4414 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4415 ssh2_pkt_addstring(ssh
, s
->username
);
4416 ssh2_pkt_addstring(ssh
, "ssh-connection");/* service requested */
4417 ssh2_pkt_addstring(ssh
, "none"); /* method */
4419 s
->type
= AUTH_TYPE_NONE
;
4421 s
->we_are_in
= FALSE
;
4423 s
->tried_pubkey_config
= FALSE
;
4424 s
->tried_agent
= FALSE
;
4425 s
->tried_keyb_inter
= FALSE
;
4426 s
->kbd_inter_running
= FALSE
;
4427 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
4428 if (!filename_is_null(ssh
->cfg
.keyfile
)) {
4430 logeventf(ssh
, "Reading private key file \"%.150s\"",
4431 filename_to_str(&ssh
->cfg
.keyfile
));
4432 keytype
= key_type(&ssh
->cfg
.keyfile
);
4433 if (keytype
== SSH_KEYTYPE_SSH2
) {
4435 ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
, NULL
,
4436 &s
->publickey_bloblen
);
4439 logeventf(ssh
, "Unable to use this key file (%s)",
4440 key_type_to_str(keytype
));
4441 msgbuf
= dupprintf("Unable to use key file \"%.150s\""
4443 filename_to_str(&ssh
->cfg
.keyfile
),
4444 key_type_to_str(keytype
));
4445 c_write_str(ssh
, msgbuf
);
4447 s
->publickey_blob
= NULL
;
4450 s
->publickey_blob
= NULL
;
4454 * Wait for the result of the last authentication request.
4457 crWaitUntilV(ispkt
);
4458 while (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_BANNER
) {
4462 * Don't show the banner if we're operating in
4463 * non-verbose non-interactive mode. (It's probably
4464 * a script, which means nobody will read the
4465 * banner _anyway_, and moreover the printing of
4466 * the banner will screw up processing on the
4467 * output of (say) plink.)
4469 if (flags
& (FLAG_VERBOSE
| FLAG_INTERACTIVE
)) {
4470 ssh2_pkt_getstring(ssh
, &banner
, &size
);
4472 c_write_untrusted(ssh
, banner
, size
);
4474 crWaitUntilV(ispkt
);
4476 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_SUCCESS
) {
4477 logevent("Access granted");
4478 s
->we_are_in
= TRUE
;
4482 if (s
->kbd_inter_running
&&
4483 ssh
->pktin
.type
== SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4485 * This is either a further set-of-prompts packet
4486 * in keyboard-interactive authentication, or it's
4487 * the same one and we came back here with `gotit'
4488 * set. In the former case, we must reset the
4489 * curr_prompt variable.
4493 } else if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_FAILURE
) {
4494 bombout((ssh
,"Strange packet received during authentication: type %d",
4502 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4503 * we can look at the string in it and know what we can
4504 * helpfully try next.
4506 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
) {
4509 ssh2_pkt_getstring(ssh
, &methods
, &methlen
);
4510 s
->kbd_inter_running
= FALSE
;
4511 if (!ssh2_pkt_getbool(ssh
)) {
4513 * We have received an unequivocal Access
4514 * Denied. This can translate to a variety of
4517 * - if we'd just tried "none" authentication,
4518 * it's not worth printing anything at all
4520 * - if we'd just tried a public key _offer_,
4521 * the message should be "Server refused our
4522 * key" (or no message at all if the key
4523 * came from Pageant)
4525 * - if we'd just tried anything else, the
4526 * message really should be "Access denied".
4528 * Additionally, if we'd just tried password
4529 * authentication, we should break out of this
4530 * whole loop so as to go back to the username
4533 if (s
->type
== AUTH_TYPE_NONE
) {
4535 } else if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
||
4536 s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_QUIET
) {
4537 if (s
->type
== AUTH_TYPE_PUBLICKEY_OFFER_LOUD
)
4538 c_write_str(ssh
, "Server refused our key\r\n");
4539 logevent("Server refused public key");
4540 } else if (s
->type
==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
) {
4541 /* server declined keyboard-interactive; ignore */
4543 c_write_str(ssh
, "Access denied\r\n");
4544 logevent("Access denied");
4545 if (s
->type
== AUTH_TYPE_PASSWORD
) {
4546 s
->we_are_in
= FALSE
;
4551 c_write_str(ssh
, "Further authentication required\r\n");
4552 logevent("Further authentication required");
4556 in_commasep_string("publickey", methods
, methlen
);
4558 in_commasep_string("password", methods
, methlen
);
4559 s
->can_keyb_inter
= ssh
->cfg
.try_ki_auth
&&
4560 in_commasep_string("keyboard-interactive", methods
, methlen
);
4564 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4567 * Most password/passphrase prompts will be
4568 * non-echoing, so we set this to 0 by default.
4569 * Exception is that some keyboard-interactive prompts
4570 * can be echoing, in which case we'll set this to 1.
4574 if (!s
->method
&& s
->can_pubkey
&&
4575 agent_exists() && !s
->tried_agent
) {
4577 * Attempt public-key authentication using Pageant.
4582 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4583 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4585 s
->tried_agent
= TRUE
;
4587 logevent("Pageant is running. Requesting keys.");
4589 /* Request the keys held by the agent. */
4590 PUT_32BIT(s
->request
, 1);
4591 s
->request
[4] = SSH2_AGENTC_REQUEST_IDENTITIES
;
4592 agent_query(s
->request
, 5, &r
, &s
->responselen
);
4593 s
->response
= (unsigned char *) r
;
4594 if (s
->response
&& s
->responselen
>= 5 &&
4595 s
->response
[4] == SSH2_AGENT_IDENTITIES_ANSWER
) {
4596 s
->p
= s
->response
+ 5;
4597 s
->nkeys
= GET_32BIT(s
->p
);
4601 sprintf(buf
, "Pageant has %d SSH2 keys", s
->nkeys
);
4604 for (s
->keyi
= 0; s
->keyi
< s
->nkeys
; s
->keyi
++) {
4609 sprintf(buf
, "Trying Pageant key #%d", s
->keyi
);
4612 s
->pklen
= GET_32BIT(s
->p
);
4614 if (s
->publickey_blob
&&
4615 s
->pklen
== s
->publickey_bloblen
&&
4616 !memcmp(s
->p
, s
->publickey_blob
,
4617 s
->publickey_bloblen
)) {
4618 logevent("This key matches configured key file");
4619 s
->tried_pubkey_config
= 1;
4621 s
->pkblob
= (char *)s
->p
;
4623 s
->alglen
= GET_32BIT(s
->pkblob
);
4624 s
->alg
= s
->pkblob
+ 4;
4625 s
->commentlen
= GET_32BIT(s
->p
);
4627 s
->commentp
= (char *)s
->p
;
4628 s
->p
+= s
->commentlen
;
4629 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4630 ssh2_pkt_addstring(ssh
, s
->username
);
4631 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4632 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4633 ssh2_pkt_addbool(ssh
, FALSE
); /* no signature included */
4634 ssh2_pkt_addstring_start(ssh
);
4635 ssh2_pkt_addstring_data(ssh
, s
->alg
, s
->alglen
);
4636 ssh2_pkt_addstring_start(ssh
);
4637 ssh2_pkt_addstring_data(ssh
, s
->pkblob
, s
->pklen
);
4640 crWaitUntilV(ispkt
);
4641 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4642 logevent("Key refused");
4646 if (flags
& FLAG_VERBOSE
) {
4647 c_write_str(ssh
, "Authenticating with "
4649 c_write(ssh
, s
->commentp
, s
->commentlen
);
4650 c_write_str(ssh
, "\" from agent\r\n");
4654 * Server is willing to accept the key.
4655 * Construct a SIGN_REQUEST.
4657 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4658 ssh2_pkt_addstring(ssh
, s
->username
);
4659 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4660 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4661 ssh2_pkt_addbool(ssh
, TRUE
);
4662 ssh2_pkt_addstring_start(ssh
);
4663 ssh2_pkt_addstring_data(ssh
, s
->alg
, s
->alglen
);
4664 ssh2_pkt_addstring_start(ssh
);
4665 ssh2_pkt_addstring_data(ssh
, s
->pkblob
, s
->pklen
);
4667 s
->siglen
= ssh
->pktout
.length
- 5 + 4 + 20;
4668 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
4670 s
->len
= 1; /* message type */
4671 s
->len
+= 4 + s
->pklen
; /* key blob */
4672 s
->len
+= 4 + s
->siglen
; /* data to sign */
4673 s
->len
+= 4; /* flags */
4674 s
->agentreq
= smalloc(4 + s
->len
);
4675 PUT_32BIT(s
->agentreq
, s
->len
);
4676 s
->q
= s
->agentreq
+ 4;
4677 *s
->q
++ = SSH2_AGENTC_SIGN_REQUEST
;
4678 PUT_32BIT(s
->q
, s
->pklen
);
4680 memcpy(s
->q
, s
->pkblob
, s
->pklen
);
4682 PUT_32BIT(s
->q
, s
->siglen
);
4684 /* Now the data to be signed... */
4685 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
4686 PUT_32BIT(s
->q
, 20);
4689 memcpy(s
->q
, ssh
->v2_session_id
, 20);
4691 memcpy(s
->q
, ssh
->pktout
.data
+ 5,
4692 ssh
->pktout
.length
- 5);
4693 s
->q
+= ssh
->pktout
.length
- 5;
4694 /* And finally the (zero) flags word. */
4696 agent_query(s
->agentreq
, s
->len
+ 4, &vret
, &s
->retlen
);
4700 if (s
->ret
[4] == SSH2_AGENT_SIGN_RESPONSE
) {
4701 logevent("Sending Pageant's response");
4702 ssh2_add_sigblob(ssh
, s
->pkblob
, s
->pklen
,
4704 GET_32BIT(s
->ret
+ 5));
4710 ("Pageant failed to answer challenge");
4720 if (!s
->method
&& s
->can_pubkey
&& s
->publickey_blob
4721 && !s
->tried_pubkey_config
) {
4722 unsigned char *pub_blob
;
4723 char *algorithm
, *comment
;
4726 s
->tried_pubkey_config
= TRUE
;
4728 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4729 ssh
->pkt_ctx
|= SSH2_PKTCTX_PUBLICKEY
;
4732 * Try the public key supplied in the configuration.
4734 * First, offer the public blob to see if the server is
4735 * willing to accept it.
4738 (unsigned char *)ssh2_userkey_loadpub(&ssh
->cfg
.keyfile
,
4742 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4743 ssh2_pkt_addstring(ssh
, s
->username
);
4744 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4745 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4746 ssh2_pkt_addbool(ssh
, FALSE
); /* no signature included */
4747 ssh2_pkt_addstring(ssh
, algorithm
);
4748 ssh2_pkt_addstring_start(ssh
);
4749 ssh2_pkt_addstring_data(ssh
, (char *)pub_blob
,
4752 logevent("Offered public key"); /* FIXME */
4754 crWaitUntilV(ispkt
);
4755 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_PK_OK
) {
4757 s
->type
= AUTH_TYPE_PUBLICKEY_OFFER_LOUD
;
4758 continue; /* key refused; give up on it */
4761 logevent("Offer of public key accepted");
4763 * Actually attempt a serious authentication using
4766 if (ssh2_userkey_encrypted(&ssh
->cfg
.keyfile
, &comment
)) {
4767 sprintf(s
->pwprompt
,
4768 "Passphrase for key \"%.100s\": ",
4774 c_write_str(ssh
, "Authenticating with public key \"");
4775 c_write_str(ssh
, comment
);
4776 c_write_str(ssh
, "\"\r\n");
4777 s
->method
= AUTH_PUBLICKEY_FILE
;
4781 if (!s
->method
&& s
->can_keyb_inter
&& !s
->tried_keyb_inter
) {
4782 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
4783 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4784 s
->tried_keyb_inter
= TRUE
;
4786 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4787 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4789 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4790 ssh2_pkt_addstring(ssh
, s
->username
);
4791 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4792 ssh2_pkt_addstring(ssh
, "keyboard-interactive"); /* method */
4793 ssh2_pkt_addstring(ssh
, ""); /* lang */
4794 ssh2_pkt_addstring(ssh
, "");
4797 crWaitUntilV(ispkt
);
4798 if (ssh
->pktin
.type
!= SSH2_MSG_USERAUTH_INFO_REQUEST
) {
4799 if (ssh
->pktin
.type
== SSH2_MSG_USERAUTH_FAILURE
)
4801 logevent("Keyboard-interactive authentication refused");
4802 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
;
4806 s
->kbd_inter_running
= TRUE
;
4810 if (s
->kbd_inter_running
) {
4811 s
->method
= AUTH_KEYBOARD_INTERACTIVE
;
4812 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
4813 s
->tried_keyb_inter
= TRUE
;
4815 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4816 ssh
->pkt_ctx
|= SSH2_PKTCTX_KBDINTER
;
4818 if (s
->curr_prompt
== 0) {
4820 * We've got a fresh USERAUTH_INFO_REQUEST.
4821 * Display header data, and start going through
4824 char *name
, *inst
, *lang
;
4825 int name_len
, inst_len
, lang_len
;
4827 ssh2_pkt_getstring(ssh
, &name
, &name_len
);
4828 ssh2_pkt_getstring(ssh
, &inst
, &inst_len
);
4829 ssh2_pkt_getstring(ssh
, &lang
, &lang_len
);
4831 c_write_untrusted(ssh
, name
, name_len
);
4832 c_write_str(ssh
, "\r\n");
4835 c_write_untrusted(ssh
, inst
, inst_len
);
4836 c_write_str(ssh
, "\r\n");
4838 s
->num_prompts
= ssh2_pkt_getuint32(ssh
);
4842 * If there are prompts remaining in the packet,
4843 * display one and get a response.
4845 if (s
->curr_prompt
< s
->num_prompts
) {
4849 ssh2_pkt_getstring(ssh
, &prompt
, &prompt_len
);
4850 if (prompt_len
> 0) {
4851 strncpy(s
->pwprompt
, prompt
, sizeof(s
->pwprompt
));
4852 s
->pwprompt
[prompt_len
< sizeof(s
->pwprompt
) ?
4853 prompt_len
: sizeof(s
->pwprompt
)-1] = '\0';
4856 "<server failed to send prompt>: ");
4858 s
->echo
= ssh2_pkt_getbool(ssh
);
4864 if (!s
->method
&& s
->can_passwd
) {
4865 s
->method
= AUTH_PASSWORD
;
4866 ssh
->pkt_ctx
&= ~SSH2_PKTCTX_AUTH_MASK
;
4867 ssh
->pkt_ctx
|= SSH2_PKTCTX_PASSWORD
;
4868 sprintf(s
->pwprompt
, "%.90s@%.90s's password: ", s
->username
,
4875 if (!ssh_get_line(s
->pwprompt
, s
->password
,
4876 sizeof(s
->password
), TRUE
)) {
4878 * get_line failed to get a password (for
4879 * example because one was supplied on the
4880 * command line which has already failed to
4883 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
4884 ssh2_pkt_adduint32(ssh
,SSH2_DISCONNECT_BY_APPLICATION
);
4885 ssh2_pkt_addstring(ssh
, "No more passwords available"
4887 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
4889 logevent("Unable to authenticate");
4890 connection_fatal(ssh
->frontend
,
4891 "Unable to authenticate");
4892 ssh
->state
= SSH_STATE_CLOSED
;
4896 int ret
; /* need not be saved across crReturn */
4897 c_write_untrusted(ssh
, s
->pwprompt
, strlen(s
->pwprompt
));
4900 setup_userpass_input(ssh
, s
->password
,
4901 sizeof(s
->password
), s
->echo
);
4903 crWaitUntilV(!ispkt
);
4904 ret
= process_userpass_input(ssh
, in
, inlen
);
4908 c_write_str(ssh
, "\r\n");
4912 if (s
->method
== AUTH_PUBLICKEY_FILE
) {
4914 * We have our passphrase. Now try the actual authentication.
4916 struct ssh2_userkey
*key
;
4918 key
= ssh2_load_userkey(&ssh
->cfg
.keyfile
, s
->password
);
4919 if (key
== SSH2_WRONG_PASSPHRASE
|| key
== NULL
) {
4920 if (key
== SSH2_WRONG_PASSPHRASE
) {
4921 c_write_str(ssh
, "Wrong passphrase\r\n");
4922 s
->tried_pubkey_config
= FALSE
;
4924 c_write_str(ssh
, "Unable to load private key\r\n");
4925 s
->tried_pubkey_config
= TRUE
;
4927 /* Send a spurious AUTH_NONE to return to the top. */
4928 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4929 ssh2_pkt_addstring(ssh
, s
->username
);
4930 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4931 ssh2_pkt_addstring(ssh
, "none"); /* method */
4933 s
->type
= AUTH_TYPE_NONE
;
4935 unsigned char *pkblob
, *sigblob
, *sigdata
;
4936 int pkblob_len
, sigblob_len
, sigdata_len
;
4940 * We have loaded the private key and the server
4941 * has announced that it's willing to accept it.
4942 * Hallelujah. Generate a signature and send it.
4944 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
4945 ssh2_pkt_addstring(ssh
, s
->username
);
4946 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
4947 ssh2_pkt_addstring(ssh
, "publickey"); /* method */
4948 ssh2_pkt_addbool(ssh
, TRUE
);
4949 ssh2_pkt_addstring(ssh
, key
->alg
->name
);
4950 pkblob
= key
->alg
->public_blob(key
->data
, &pkblob_len
);
4951 ssh2_pkt_addstring_start(ssh
);
4952 ssh2_pkt_addstring_data(ssh
, (char *)pkblob
, pkblob_len
);
4955 * The data to be signed is:
4959 * followed by everything so far placed in the
4962 sigdata_len
= ssh
->pktout
.length
- 5 + 4 + 20;
4963 if (ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)
4965 sigdata
= smalloc(sigdata_len
);
4967 if (!(ssh
->remote_bugs
& BUG_SSH2_PK_SESSIONID
)) {
4968 PUT_32BIT(sigdata
+p
, 20);
4971 memcpy(sigdata
+p
, ssh
->v2_session_id
, 20); p
+= 20;
4972 memcpy(sigdata
+p
, ssh
->pktout
.data
+ 5,
4973 ssh
->pktout
.length
- 5);
4974 p
+= ssh
->pktout
.length
- 5;
4975 assert(p
== sigdata_len
);
4976 sigblob
= key
->alg
->sign(key
->data
, (char *)sigdata
,
4977 sigdata_len
, &sigblob_len
);
4978 ssh2_add_sigblob(ssh
, pkblob
, pkblob_len
,
4979 sigblob
, sigblob_len
);
4985 s
->type
= AUTH_TYPE_PUBLICKEY
;
4987 } else if (s
->method
== AUTH_PASSWORD
) {
4989 * We send the password packet lumped tightly together with
4990 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
4991 * string long enough to make the total length of the two
4992 * packets constant. This should ensure that a passive
4993 * listener doing traffic analyis can't work out the length
4996 * For this to work, we need an assumption about the
4997 * maximum length of the password packet. I think 256 is
4998 * pretty conservative. Anyone using a password longer than
4999 * that probably doesn't have much to worry about from
5000 * people who find out how long their password is!
5002 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_REQUEST
);
5003 ssh2_pkt_addstring(ssh
, s
->username
);
5004 ssh2_pkt_addstring(ssh
, "ssh-connection"); /* service requested */
5005 ssh2_pkt_addstring(ssh
, "password");
5006 ssh2_pkt_addbool(ssh
, FALSE
);
5007 ssh2_pkt_addstring(ssh
, s
->password
);
5008 memset(s
->password
, 0, sizeof(s
->password
));
5009 ssh2_pkt_defer(ssh
);
5011 * We'll include a string that's an exact multiple of the
5012 * cipher block size. If the cipher is NULL for some
5013 * reason, we don't do this trick at all because we gain
5016 if (ssh
->cscipher
) {
5019 stringlen
= (256 - ssh
->deferred_len
);
5020 stringlen
+= ssh
->cscipher
->blksize
- 1;
5021 stringlen
-= (stringlen
% ssh
->cscipher
->blksize
);
5024 * Temporarily disable actual compression,
5025 * so we can guarantee to get this string
5026 * exactly the length we want it. The
5027 * compression-disabling routine should
5028 * return an integer indicating how many
5029 * bytes we should adjust our string length
5033 ssh
->cscomp
->disable_compression(ssh
->cs_comp_ctx
);
5035 ssh2_pkt_init(ssh
, SSH2_MSG_IGNORE
);
5036 ssh2_pkt_addstring_start(ssh
);
5037 for (i
= 0; i
< stringlen
; i
++) {
5038 char c
= (char) random_byte();
5039 ssh2_pkt_addstring_data(ssh
, &c
, 1);
5041 ssh2_pkt_defer(ssh
);
5043 ssh_pkt_defersend(ssh
);
5044 logevent("Sent password");
5045 s
->type
= AUTH_TYPE_PASSWORD
;
5046 } else if (s
->method
== AUTH_KEYBOARD_INTERACTIVE
) {
5047 if (s
->curr_prompt
== 0) {
5048 ssh2_pkt_init(ssh
, SSH2_MSG_USERAUTH_INFO_RESPONSE
);
5049 ssh2_pkt_adduint32(ssh
, s
->num_prompts
);
5051 if (s
->need_pw
) { /* only add pw if we just got one! */
5052 ssh2_pkt_addstring(ssh
, s
->password
);
5053 memset(s
->password
, 0, sizeof(s
->password
));
5056 if (s
->curr_prompt
>= s
->num_prompts
) {
5060 * If there are prompts remaining, we set
5061 * `gotit' so that we won't attempt to get
5062 * another packet. Then we go back round the
5063 * loop and will end up retrieving another
5064 * prompt out of the existing packet. Funky or
5069 s
->type
= AUTH_TYPE_KEYBOARD_INTERACTIVE
;
5071 c_write_str(ssh
, "No supported authentication methods"
5072 " left to try!\r\n");
5073 logevent("No supported authentications offered."
5075 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5076 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
5077 ssh2_pkt_addstring(ssh
, "No supported authentication"
5078 " methods available");
5079 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5081 ssh
->state
= SSH_STATE_CLOSED
;
5085 } while (!s
->we_are_in
);
5088 * Now we're authenticated for the connection protocol. The
5089 * connection protocol will automatically have started at this
5090 * point; there's no need to send SERVICE_REQUEST.
5094 * So now create a channel with a session in it.
5096 ssh
->channels
= newtree234(ssh_channelcmp
);
5097 ssh
->mainchan
= smalloc(sizeof(struct ssh_channel
));
5098 ssh
->mainchan
->ssh
= ssh
;
5099 ssh
->mainchan
->localid
= alloc_channel_id(ssh
);
5100 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN
);
5101 ssh2_pkt_addstring(ssh
, "session");
5102 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->localid
);
5103 ssh
->mainchan
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5104 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->v
.v2
.locwindow
);/* our window size */
5105 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
5107 crWaitUntilV(ispkt
);
5108 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5109 bombout((ssh
,"Server refused to open a session"));
5111 /* FIXME: error data comes back in FAILURE packet */
5113 if (ssh2_pkt_getuint32(ssh
) != ssh
->mainchan
->localid
) {
5114 bombout((ssh
,"Server's channel confirmation cited wrong channel"));
5117 ssh
->mainchan
->remoteid
= ssh2_pkt_getuint32(ssh
);
5118 ssh
->mainchan
->type
= CHAN_MAINSESSION
;
5119 ssh
->mainchan
->closes
= 0;
5120 ssh
->mainchan
->v
.v2
.remwindow
= ssh2_pkt_getuint32(ssh
);
5121 ssh
->mainchan
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32(ssh
);
5122 bufchain_init(&ssh
->mainchan
->v
.v2
.outbuffer
);
5123 add234(ssh
->channels
, ssh
->mainchan
);
5124 logevent("Opened channel for session");
5127 * Potentially enable X11 forwarding.
5129 if (ssh
->cfg
.x11_forward
) {
5130 char proto
[20], data
[64];
5131 logevent("Requesting X11 forwarding");
5132 ssh
->x11auth
= x11_invent_auth(proto
, sizeof(proto
),
5133 data
, sizeof(data
), ssh
->cfg
.x11_auth
);
5134 x11_get_real_auth(ssh
->x11auth
, ssh
->cfg
.x11_display
);
5135 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5136 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5137 ssh2_pkt_addstring(ssh
, "x11-req");
5138 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5139 ssh2_pkt_addbool(ssh
, 0); /* many connections */
5140 ssh2_pkt_addstring(ssh
, proto
);
5141 ssh2_pkt_addstring(ssh
, data
);
5142 ssh2_pkt_adduint32(ssh
, x11_get_screen_number(ssh
->cfg
.x11_display
));
5146 crWaitUntilV(ispkt
);
5147 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5148 unsigned i
= ssh2_pkt_getuint32(ssh
);
5149 struct ssh_channel
*c
;
5150 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5152 continue; /* nonexistent channel */
5153 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5155 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5157 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5158 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5159 bombout((ssh
,"Unexpected response to X11 forwarding request:"
5160 " packet type %d", ssh
->pktin
.type
));
5163 logevent("X11 forwarding refused");
5165 logevent("X11 forwarding enabled");
5166 ssh
->X11_fwd_enabled
= TRUE
;
5171 * Enable port forwardings.
5176 int sport
,dport
,sserv
,dserv
;
5177 char sports
[256], dports
[256], saddr
[256], host
[256];
5179 ssh
->rportfwds
= newtree234(ssh_rportcmp_ssh2
);
5180 /* Add port forwardings. */
5181 ssh
->portfwd_strptr
= ssh
->cfg
.portfwd
;
5182 while (*ssh
->portfwd_strptr
) {
5183 type
= *ssh
->portfwd_strptr
++;
5186 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= '\t') {
5187 if (*ssh
->portfwd_strptr
== ':') {
5189 * We've seen a colon in the middle of the
5190 * source port number. This means that
5191 * everything we've seen until now is the
5192 * source _address_, so we'll move it into
5193 * saddr and start sports from the beginning
5196 ssh
->portfwd_strptr
++;
5198 strcpy(saddr
, sports
);
5201 if (n
< 255) sports
[n
++] = *ssh
->portfwd_strptr
++;
5204 if (*ssh
->portfwd_strptr
== '\t')
5205 ssh
->portfwd_strptr
++;
5207 while (*ssh
->portfwd_strptr
&& *ssh
->portfwd_strptr
!= ':') {
5208 if (n
< 255) host
[n
++] = *ssh
->portfwd_strptr
++;
5211 if (*ssh
->portfwd_strptr
== ':')
5212 ssh
->portfwd_strptr
++;
5214 while (*ssh
->portfwd_strptr
) {
5215 if (n
< 255) dports
[n
++] = *ssh
->portfwd_strptr
++;
5218 ssh
->portfwd_strptr
++;
5219 dport
= atoi(dports
);
5223 dport
= net_service_lookup(dports
);
5225 logeventf(ssh
, "Service lookup failed for destination"
5226 " port \"%s\"", dports
);
5229 sport
= atoi(sports
);
5233 sport
= net_service_lookup(sports
);
5235 logeventf(ssh
, "Service lookup failed for source"
5236 " port \"%s\"", sports
);
5239 if (sport
&& dport
) {
5241 pfd_addforward(host
, dport
, *saddr ? saddr
: NULL
,
5242 sport
, ssh
, &ssh
->cfg
);
5243 logeventf(ssh
, "Local port %.*s%.*s%.*s%.*s%d%.*s"
5244 " forwarding to %s:%.*s%.*s%d%.*s",
5245 (int)(*saddr?
strlen(saddr
):0), *saddr?saddr
:NULL
,
5246 (int)(*saddr?
1:0), ":",
5247 (int)(sserv ?
strlen(sports
) : 0), sports
,
5248 sserv
, "(", sport
, sserv
, ")",
5250 (int)(dserv ?
strlen(dports
) : 0), dports
,
5251 dserv
, "(", dport
, dserv
, ")");
5253 struct ssh_rportfwd
*pf
;
5254 pf
= smalloc(sizeof(*pf
));
5255 strcpy(pf
->dhost
, host
);
5258 if (add234(ssh
->rportfwds
, pf
) != pf
) {
5259 logeventf(ssh
, "Duplicate remote port forwarding"
5260 " to %s:%d", host
, dport
);
5263 logeventf(ssh
, "Requesting remote port "
5264 "%.*s%.*s%.*s%.*s%d%.*s"
5265 " forward to %s:%.*s%.*s%d%.*s",
5266 (int)(*saddr?
strlen(saddr
):0),
5268 (int)(*saddr?
1:0), ":",
5269 (int)(sserv ?
strlen(sports
) : 0), sports
,
5270 sserv
, "(", sport
, sserv
, ")",
5272 (int)(dserv ?
strlen(dports
) : 0), dports
,
5273 dserv
, "(", dport
, dserv
, ")");
5274 ssh2_pkt_init(ssh
, SSH2_MSG_GLOBAL_REQUEST
);
5275 ssh2_pkt_addstring(ssh
, "tcpip-forward");
5276 ssh2_pkt_addbool(ssh
, 1);/* want reply */
5278 ssh2_pkt_addstring(ssh
, saddr
);
5279 if (ssh
->cfg
.rport_acceptall
)
5280 ssh2_pkt_addstring(ssh
, "0.0.0.0");
5282 ssh2_pkt_addstring(ssh
, "127.0.0.1");
5283 ssh2_pkt_adduint32(ssh
, sport
);
5287 crWaitUntilV(ispkt
);
5288 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5289 unsigned i
= ssh2_pkt_getuint32(ssh
);
5290 struct ssh_channel
*c
;
5291 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5293 continue;/* nonexistent channel */
5294 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5296 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5298 if (ssh
->pktin
.type
!= SSH2_MSG_REQUEST_SUCCESS
) {
5299 if (ssh
->pktin
.type
!= SSH2_MSG_REQUEST_FAILURE
) {
5300 bombout((ssh
,"Unexpected response to port "
5301 "forwarding request: packet type %d",
5305 logevent("Server refused this port forwarding");
5307 logevent("Remote port forwarding enabled");
5316 * Potentially enable agent forwarding.
5318 if (ssh
->cfg
.agentfwd
&& agent_exists()) {
5319 logevent("Requesting OpenSSH-style agent forwarding");
5320 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5321 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
5322 ssh2_pkt_addstring(ssh
, "auth-agent-req@openssh.com");
5323 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5327 crWaitUntilV(ispkt
);
5328 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5329 unsigned i
= ssh2_pkt_getuint32(ssh
);
5330 struct ssh_channel
*c
;
5331 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5333 continue; /* nonexistent channel */
5334 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5336 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5338 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5339 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5340 bombout((ssh
,"Unexpected response to agent forwarding request:"
5341 " packet type %d", ssh
->pktin
.type
));
5344 logevent("Agent forwarding refused");
5346 logevent("Agent forwarding enabled");
5347 ssh
->agentfwd_enabled
= TRUE
;
5352 * Now allocate a pty for the session.
5354 if (!ssh
->cfg
.nopty
) {
5355 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5356 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
); /* recipient channel */
5357 ssh2_pkt_addstring(ssh
, "pty-req");
5358 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5359 ssh2_pkt_addstring(ssh
, ssh
->cfg
.termtype
);
5360 ssh2_pkt_adduint32(ssh
, ssh
->term_width
);
5361 ssh2_pkt_adduint32(ssh
, ssh
->term_height
);
5362 ssh2_pkt_adduint32(ssh
, 0); /* pixel width */
5363 ssh2_pkt_adduint32(ssh
, 0); /* pixel height */
5364 ssh2_pkt_addstring_start(ssh
);
5365 ssh2_pkt_addstring_data(ssh
, "\0", 1); /* TTY_OP_END, no special options */
5367 ssh
->state
= SSH_STATE_INTERMED
;
5370 crWaitUntilV(ispkt
);
5371 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5372 unsigned i
= ssh2_pkt_getuint32(ssh
);
5373 struct ssh_channel
*c
;
5374 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5376 continue; /* nonexistent channel */
5377 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5379 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5381 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5382 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5383 bombout((ssh
,"Unexpected response to pty request:"
5384 " packet type %d", ssh
->pktin
.type
));
5387 c_write_str(ssh
, "Server refused to allocate pty\r\n");
5388 ssh
->editing
= ssh
->echoing
= 1;
5390 logevent("Allocated pty");
5393 ssh
->editing
= ssh
->echoing
= 1;
5397 * Start a shell or a remote command. We may have to attempt
5398 * this twice if the config data has provided a second choice
5405 if (ssh
->fallback_cmd
) {
5406 subsys
= ssh
->cfg
.ssh_subsys2
;
5407 cmd
= ssh
->cfg
.remote_cmd_ptr2
;
5409 subsys
= ssh
->cfg
.ssh_subsys
;
5410 cmd
= ssh
->cfg
.remote_cmd_ptr
;
5413 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
5414 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
); /* recipient channel */
5416 ssh2_pkt_addstring(ssh
, "subsystem");
5417 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5418 ssh2_pkt_addstring(ssh
, cmd
);
5420 ssh2_pkt_addstring(ssh
, "exec");
5421 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5422 ssh2_pkt_addstring(ssh
, cmd
);
5424 ssh2_pkt_addstring(ssh
, "shell");
5425 ssh2_pkt_addbool(ssh
, 1); /* want reply */
5429 crWaitUntilV(ispkt
);
5430 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5431 unsigned i
= ssh2_pkt_getuint32(ssh
);
5432 struct ssh_channel
*c
;
5433 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5435 continue; /* nonexistent channel */
5436 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5438 } while (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
5439 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_SUCCESS
) {
5440 if (ssh
->pktin
.type
!= SSH2_MSG_CHANNEL_FAILURE
) {
5441 bombout((ssh
,"Unexpected response to shell/command request:"
5442 " packet type %d", ssh
->pktin
.type
));
5446 * We failed to start the command. If this is the
5447 * fallback command, we really are finished; if it's
5448 * not, and if the fallback command exists, try falling
5449 * back to it before complaining.
5451 if (!ssh
->fallback_cmd
&& ssh
->cfg
.remote_cmd_ptr2
!= NULL
) {
5452 logevent("Primary command failed; attempting fallback");
5453 ssh
->fallback_cmd
= TRUE
;
5456 bombout((ssh
,"Server refused to start a shell/command"));
5459 logevent("Started a shell/command");
5464 ssh
->state
= SSH_STATE_SESSION
;
5465 if (ssh
->size_needed
)
5466 ssh_size(ssh
, ssh
->term_width
, ssh
->term_height
);
5467 if (ssh
->eof_needed
)
5468 ssh_special(ssh
, TS_EOF
);
5474 ldisc_send(ssh
->ldisc
, NULL
, 0, 0);/* cause ldisc to notice changes */
5478 s
->try_send
= FALSE
;
5480 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_DATA
||
5481 ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
) {
5484 unsigned i
= ssh2_pkt_getuint32(ssh
);
5485 struct ssh_channel
*c
;
5486 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5488 continue; /* nonexistent channel */
5489 if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EXTENDED_DATA
&&
5490 ssh2_pkt_getuint32(ssh
) != SSH2_EXTENDED_DATA_STDERR
)
5491 continue; /* extended but not stderr */
5492 ssh2_pkt_getstring(ssh
, &data
, &length
);
5495 c
->v
.v2
.locwindow
-= length
;
5497 case CHAN_MAINSESSION
:
5499 from_backend(ssh
->frontend
, ssh
->pktin
.type
==
5500 SSH2_MSG_CHANNEL_EXTENDED_DATA
,
5504 bufsize
= x11_send(c
->u
.x11
.s
, data
, length
);
5507 bufsize
= pfd_send(c
->u
.pfd
.s
, data
, length
);
5510 while (length
> 0) {
5511 if (c
->u
.a
.lensofar
< 4) {
5512 int l
= min(4 - c
->u
.a
.lensofar
, length
);
5513 memcpy(c
->u
.a
.msglen
+ c
->u
.a
.lensofar
,
5517 c
->u
.a
.lensofar
+= l
;
5519 if (c
->u
.a
.lensofar
== 4) {
5521 4 + GET_32BIT(c
->u
.a
.msglen
);
5522 c
->u
.a
.message
= smalloc(c
->u
.a
.totallen
);
5523 memcpy(c
->u
.a
.message
, c
->u
.a
.msglen
, 4);
5525 if (c
->u
.a
.lensofar
>= 4 && length
> 0) {
5527 min(c
->u
.a
.totallen
- c
->u
.a
.lensofar
,
5529 memcpy(c
->u
.a
.message
+ c
->u
.a
.lensofar
,
5533 c
->u
.a
.lensofar
+= l
;
5535 if (c
->u
.a
.lensofar
== c
->u
.a
.totallen
) {
5536 void *reply
, *sentreply
;
5538 agent_query(c
->u
.a
.message
,
5539 c
->u
.a
.totallen
, &reply
,
5544 /* Fake SSH_AGENT_FAILURE. */
5545 sentreply
= "\0\0\0\1\5";
5548 ssh2_add_channel_data(c
, sentreply
, replylen
);
5552 sfree(c
->u
.a
.message
);
5553 c
->u
.a
.lensofar
= 0;
5560 * If we are not buffering too much data,
5561 * enlarge the window again at the remote side.
5563 if (bufsize
< OUR_V2_WINSIZE
)
5564 ssh2_set_window(c
, OUR_V2_WINSIZE
- bufsize
);
5566 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_EOF
) {
5567 unsigned i
= ssh2_pkt_getuint32(ssh
);
5568 struct ssh_channel
*c
;
5570 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5572 continue; /* nonexistent channel */
5574 if (c
->type
== CHAN_X11
) {
5576 * Remote EOF on an X11 channel means we should
5577 * wrap up and close the channel ourselves.
5579 x11_close(c
->u
.x11
.s
);
5581 } else if (c
->type
== CHAN_AGENT
) {
5583 } else if (c
->type
== CHAN_SOCKDATA
) {
5584 pfd_close(c
->u
.pfd
.s
);
5587 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_CLOSE
) {
5588 unsigned i
= ssh2_pkt_getuint32(ssh
);
5589 struct ssh_channel
*c
;
5591 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5592 if (!c
|| ((int)c
->remoteid
) == -1) {
5593 bombout((ssh
,"Received CHANNEL_CLOSE for %s channel %d\n",
5594 c ?
"half-open" : "nonexistent", i
));
5596 /* Do pre-close processing on the channel. */
5598 case CHAN_MAINSESSION
:
5599 break; /* nothing to see here, move along */
5601 if (c
->u
.x11
.s
!= NULL
)
5602 x11_close(c
->u
.x11
.s
);
5609 if (c
->u
.pfd
.s
!= NULL
)
5610 pfd_close(c
->u
.pfd
.s
);
5614 if (c
->closes
== 0) {
5615 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
5616 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5619 del234(ssh
->channels
, c
);
5620 bufchain_clear(&c
->v
.v2
.outbuffer
);
5624 * See if that was the last channel left open.
5626 if (count234(ssh
->channels
) == 0) {
5629 * We used to send SSH_MSG_DISCONNECT here,
5630 * because I'd believed that _every_ conforming
5631 * SSH2 connection had to end with a disconnect
5632 * being sent by at least one side; apparently
5633 * I was wrong and it's perfectly OK to
5634 * unceremoniously slam the connection shut
5635 * when you're done, and indeed OpenSSH feels
5636 * this is more polite than sending a
5637 * DISCONNECT. So now we don't.
5639 logevent("All channels closed. Disconnecting");
5640 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5641 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
5642 ssh2_pkt_addstring(ssh
, "All open channels closed");
5643 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5646 ssh
->state
= SSH_STATE_CLOSED
;
5649 continue; /* remote sends close; ignore (FIXME) */
5650 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_WINDOW_ADJUST
) {
5651 unsigned i
= ssh2_pkt_getuint32(ssh
);
5652 struct ssh_channel
*c
;
5653 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5654 if (!c
|| c
->closes
)
5655 continue; /* nonexistent or closing channel */
5656 c
->v
.v2
.remwindow
+= ssh2_pkt_getuint32(ssh
);
5658 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
) {
5659 unsigned i
= ssh2_pkt_getuint32(ssh
);
5660 struct ssh_channel
*c
;
5661 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5663 continue; /* nonexistent channel */
5664 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5665 continue; /* dunno why they're confirming this */
5666 c
->remoteid
= ssh2_pkt_getuint32(ssh
);
5667 c
->type
= CHAN_SOCKDATA
;
5668 c
->v
.v2
.remwindow
= ssh2_pkt_getuint32(ssh
);
5669 c
->v
.v2
.remmaxpkt
= ssh2_pkt_getuint32(ssh
);
5671 pfd_confirm(c
->u
.pfd
.s
);
5674 * We have a pending close on this channel,
5675 * which we decided on before the server acked
5676 * the channel open. So now we know the
5677 * remoteid, we can close it again.
5679 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_CLOSE
);
5680 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5683 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN_FAILURE
) {
5684 unsigned i
= ssh2_pkt_getuint32(ssh
);
5685 struct ssh_channel
*c
;
5686 c
= find234(ssh
->channels
, &i
, ssh_channelfind
);
5688 continue; /* nonexistent channel */
5689 if (c
->type
!= CHAN_SOCKDATA_DORMANT
)
5690 continue; /* dunno why they're failing this */
5692 logevent("Forwarded connection refused by server");
5694 pfd_close(c
->u
.pfd
.s
);
5696 del234(ssh
->channels
, c
);
5698 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_REQUEST
) {
5701 int typelen
, want_reply
;
5702 struct ssh_channel
*c
;
5704 localid
= ssh2_pkt_getuint32(ssh
);
5705 ssh2_pkt_getstring(ssh
, &type
, &typelen
);
5706 want_reply
= ssh2_pkt_getbool(ssh
);
5709 * First, check that the channel exists. Otherwise,
5710 * we can instantly disconnect with a rude message.
5712 c
= find234(ssh
->channels
, &localid
, ssh_channelfind
);
5715 sprintf(buf
, "Received channel request for nonexistent"
5716 " channel %d", localid
);
5718 ssh2_pkt_init(ssh
, SSH2_MSG_DISCONNECT
);
5719 ssh2_pkt_adduint32(ssh
, SSH2_DISCONNECT_BY_APPLICATION
);
5720 ssh2_pkt_addstring(ssh
, buf
);
5721 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5723 connection_fatal("%s", buf
);
5724 ssh
->state
= SSH_STATE_CLOSED
;
5729 * Having got the channel number, we now look at
5730 * the request type string to see if it's something
5733 if (typelen
== 11 && !memcmp(type
, "exit-status", 11) &&
5734 c
== ssh
->mainchan
) {
5735 /* We recognise "exit-status" on the primary channel. */
5737 ssh
->exitcode
= ssh2_pkt_getuint32(ssh
);
5738 sprintf(buf
, "Server sent command exit status %d",
5742 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_SUCCESS
);
5743 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5748 * This is a channel request we don't know
5749 * about, so we now either ignore the request
5750 * or respond with CHANNEL_FAILURE, depending
5754 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_FAILURE
);
5755 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5759 } else if (ssh
->pktin
.type
== SSH2_MSG_GLOBAL_REQUEST
) {
5761 int typelen
, want_reply
;
5763 ssh2_pkt_getstring(ssh
, &type
, &typelen
);
5764 want_reply
= ssh2_pkt_getbool(ssh
);
5767 * We currently don't support any global requests
5768 * at all, so we either ignore the request or
5769 * respond with REQUEST_FAILURE, depending on
5773 ssh2_pkt_init(ssh
, SSH2_MSG_REQUEST_FAILURE
);
5776 } else if (ssh
->pktin
.type
== SSH2_MSG_CHANNEL_OPEN
) {
5783 struct ssh_channel
*c
;
5784 unsigned remid
, winsize
, pktsize
;
5785 ssh2_pkt_getstring(ssh
, &type
, &typelen
);
5786 c
= smalloc(sizeof(struct ssh_channel
));
5789 remid
= ssh2_pkt_getuint32(ssh
);
5790 winsize
= ssh2_pkt_getuint32(ssh
);
5791 pktsize
= ssh2_pkt_getuint32(ssh
);
5792 ssh2_pkt_getstring(ssh
, &peeraddr
, &peeraddrlen
);
5793 port
= ssh2_pkt_getuint32(ssh
);
5795 if (typelen
== 3 && !memcmp(type
, "x11", 3)) {
5796 char *addrstr
= smalloc(peeraddrlen
+1);
5797 memcpy(addrstr
, peeraddr
, peeraddrlen
);
5798 peeraddr
[peeraddrlen
] = '\0';
5800 if (!ssh
->X11_fwd_enabled
)
5801 error
= "X11 forwarding is not enabled";
5802 else if (x11_init(&c
->u
.x11
.s
, ssh
->cfg
.x11_display
, c
,
5803 ssh
->x11auth
, addrstr
, port
,
5804 &ssh
->cfg
) != NULL
) {
5805 error
= "Unable to open an X11 connection";
5811 } else if (typelen
== 15 &&
5812 !memcmp(type
, "forwarded-tcpip", 15)) {
5813 struct ssh_rportfwd pf
, *realpf
;
5816 ssh2_pkt_getstring(ssh
, &dummy
, &dummylen
);/* skip address */
5817 pf
.sport
= ssh2_pkt_getuint32(ssh
);
5818 realpf
= find234(ssh
->rportfwds
, &pf
, NULL
);
5819 if (realpf
== NULL
) {
5820 error
= "Remote port is not recognised";
5822 char *e
= pfd_newconnect(&c
->u
.pfd
.s
, realpf
->dhost
,
5823 realpf
->dport
, c
, &ssh
->cfg
);
5824 logeventf(ssh
, "Received remote port open request"
5825 " for %s:%d", realpf
->dhost
, realpf
->dport
);
5827 logeventf(ssh
, "Port open failed: %s", e
);
5828 error
= "Port open failed";
5830 logevent("Forwarded port opened successfully");
5831 c
->type
= CHAN_SOCKDATA
;
5834 } else if (typelen
== 22 &&
5835 !memcmp(type
, "auth-agent@openssh.com", 3)) {
5836 if (!ssh
->agentfwd_enabled
)
5837 error
= "Agent forwarding is not enabled";
5839 c
->type
= CHAN_AGENT
; /* identify channel type */
5840 c
->u
.a
.lensofar
= 0;
5843 error
= "Unsupported channel type requested";
5846 c
->remoteid
= remid
;
5848 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN_FAILURE
);
5849 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5850 ssh2_pkt_adduint32(ssh
, SSH2_OPEN_CONNECT_FAILED
);
5851 ssh2_pkt_addstring(ssh
, error
);
5852 ssh2_pkt_addstring(ssh
, "en"); /* language tag */
5856 c
->localid
= alloc_channel_id(ssh
);
5858 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
5859 c
->v
.v2
.remwindow
= winsize
;
5860 c
->v
.v2
.remmaxpkt
= pktsize
;
5861 bufchain_init(&c
->v
.v2
.outbuffer
);
5862 add234(ssh
->channels
, c
);
5863 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
5864 ssh2_pkt_adduint32(ssh
, c
->remoteid
);
5865 ssh2_pkt_adduint32(ssh
, c
->localid
);
5866 ssh2_pkt_adduint32(ssh
, c
->v
.v2
.locwindow
);
5867 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
5871 bombout((ssh
,"Strange packet received: type %d", ssh
->pktin
.type
));
5876 * We have spare data. Add it to the channel buffer.
5878 ssh2_add_channel_data(ssh
->mainchan
, (char *)in
, inlen
);
5883 struct ssh_channel
*c
;
5885 * Try to send data on all channels if we can.
5887 for (i
= 0; NULL
!= (c
= index234(ssh
->channels
, i
)); i
++) {
5890 continue; /* don't send on closing channels */
5891 bufsize
= ssh2_try_send(c
);
5894 case CHAN_MAINSESSION
:
5895 /* stdin need not receive an unthrottle
5896 * notification since it will be polled */
5899 x11_unthrottle(c
->u
.x11
.s
);
5902 /* agent sockets are request/response and need no
5903 * buffer management */
5906 pfd_unthrottle(c
->u
.pfd
.s
);
5918 * Handle the top-level SSH2 protocol.
5920 static void ssh2_protocol(Ssh ssh
, unsigned char *in
, int inlen
, int ispkt
)
5922 if (do_ssh2_transport(ssh
, in
, inlen
, ispkt
) == 0)
5924 do_ssh2_authconn(ssh
, in
, inlen
, ispkt
);
5928 * Called to set up the connection.
5930 * Returns an error message, or NULL on success.
5932 static char *ssh_init(void *frontend_handle
, void **backend_handle
,
5934 char *host
, int port
, char **realhost
, int nodelay
)
5939 ssh
= smalloc(sizeof(*ssh
));
5940 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
5943 ssh
->v1_cipher_ctx
= NULL
;
5944 ssh
->crcda_ctx
= NULL
;
5945 ssh
->cscipher
= NULL
;
5946 ssh
->cs_cipher_ctx
= NULL
;
5947 ssh
->sccipher
= NULL
;
5948 ssh
->sc_cipher_ctx
= NULL
;
5950 ssh
->cs_mac_ctx
= NULL
;
5952 ssh
->sc_mac_ctx
= NULL
;
5954 ssh
->cs_comp_ctx
= NULL
;
5956 ssh
->sc_comp_ctx
= NULL
;
5958 ssh
->kex_ctx
= NULL
;
5959 ssh
->hostkey
= NULL
;
5961 ssh
->state
= SSH_STATE_PREPACKET
;
5962 ssh
->size_needed
= FALSE
;
5963 ssh
->eof_needed
= FALSE
;
5967 static const struct Packet empty
= { 0, 0, NULL
, NULL
, 0 };
5968 ssh
->pktin
= ssh
->pktout
= empty
;
5970 ssh
->deferred_send_data
= NULL
;
5971 ssh
->deferred_len
= 0;
5972 ssh
->deferred_size
= 0;
5973 ssh
->fallback_cmd
= 0;
5975 ssh
->x11auth
= NULL
;
5976 ssh
->v1_compressing
= FALSE
;
5977 ssh
->v2_outgoing_sequence
= 0;
5978 ssh
->ssh1_rdpkt_crstate
= 0;
5979 ssh
->ssh2_rdpkt_crstate
= 0;
5980 ssh
->do_ssh_init_crstate
= 0;
5981 ssh
->ssh_gotdata_crstate
= 0;
5982 ssh
->ssh1_protocol_crstate
= 0;
5983 ssh
->do_ssh1_login_crstate
= 0;
5984 ssh
->do_ssh2_transport_crstate
= 0;
5985 ssh
->do_ssh2_authconn_crstate
= 0;
5986 ssh
->do_ssh_init_state
= NULL
;
5987 ssh
->do_ssh1_login_state
= NULL
;
5988 ssh
->do_ssh2_transport_state
= NULL
;
5989 ssh
->do_ssh2_authconn_state
= NULL
;
5990 ssh
->mainchan
= NULL
;
5991 ssh
->throttled_all
= 0;
5992 ssh
->v1_stdout_throttling
= 0;
5994 *backend_handle
= ssh
;
5997 if (crypto_startup() == 0)
5998 return "Microsoft high encryption pack not installed!";
6001 ssh
->frontend
= frontend_handle
;
6002 ssh
->term_width
= ssh
->cfg
.width
;
6003 ssh
->term_height
= ssh
->cfg
.height
;
6005 ssh
->channels
= NULL
;
6006 ssh
->rportfwds
= NULL
;
6011 ssh
->v1_throttle_count
= 0;
6012 ssh
->overall_bufsize
= 0;
6013 ssh
->fallback_cmd
= 0;
6015 ssh
->protocol
= NULL
;
6017 p
= connect_to_host(ssh
, host
, port
, realhost
, nodelay
);
6024 static void ssh_free(void *handle
)
6026 Ssh ssh
= (Ssh
) handle
;
6027 struct ssh_channel
*c
;
6028 struct ssh_rportfwd
*pf
;
6030 if (ssh
->v1_cipher_ctx
)
6031 ssh
->cipher
->free_context(ssh
->v1_cipher_ctx
);
6032 if (ssh
->cs_cipher_ctx
)
6033 ssh
->cscipher
->free_context(ssh
->cs_cipher_ctx
);
6034 if (ssh
->sc_cipher_ctx
)
6035 ssh
->sccipher
->free_context(ssh
->sc_cipher_ctx
);
6036 if (ssh
->cs_mac_ctx
)
6037 ssh
->csmac
->free_context(ssh
->cs_mac_ctx
);
6038 if (ssh
->sc_mac_ctx
)
6039 ssh
->scmac
->free_context(ssh
->sc_mac_ctx
);
6040 if (ssh
->cs_comp_ctx
)
6041 ssh
->cscomp
->compress_cleanup(ssh
->cs_comp_ctx
);
6042 if (ssh
->sc_comp_ctx
)
6043 ssh
->sccomp
->compress_cleanup(ssh
->sc_comp_ctx
);
6045 dh_cleanup(ssh
->kex_ctx
);
6046 sfree(ssh
->savedhost
);
6048 if (ssh
->channels
) {
6049 while ((c
= delpos234(ssh
->channels
, 0)) != NULL
) {
6052 if (c
->u
.x11
.s
!= NULL
)
6053 x11_close(c
->u
.x11
.s
);
6056 if (c
->u
.pfd
.s
!= NULL
)
6057 pfd_close(c
->u
.pfd
.s
);
6062 freetree234(ssh
->channels
);
6065 if (ssh
->rportfwds
) {
6066 while ((pf
= delpos234(ssh
->rportfwds
, 0)) != NULL
)
6068 freetree234(ssh
->rportfwds
);
6070 sfree(ssh
->deferred_send_data
);
6072 x11_free_auth(ssh
->x11auth
);
6073 sfree(ssh
->do_ssh_init_state
);
6074 sfree(ssh
->do_ssh1_login_state
);
6075 sfree(ssh
->do_ssh2_transport_state
);
6076 sfree(ssh
->do_ssh2_authconn_state
);
6084 * Reconfigure the SSH backend.
6086 * Currently, this function does nothing very useful. In future,
6087 * however, we could do some handy things with it. For example, we
6088 * could make the port forwarding configurer active in the Change
6089 * Settings box, and this routine could close down existing
6090 * forwardings and open up new ones in response to changes.
6092 static void ssh_reconfig(void *handle
, Config
*cfg
)
6094 Ssh ssh
= (Ssh
) handle
;
6095 ssh
->cfg
= *cfg
; /* STRUCTURE COPY */
6099 * Called to send data down the Telnet connection.
6101 static int ssh_send(void *handle
, char *buf
, int len
)
6103 Ssh ssh
= (Ssh
) handle
;
6105 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
6108 ssh
->protocol(ssh
, (unsigned char *)buf
, len
, 0);
6110 return ssh_sendbuffer(ssh
);
6114 * Called to query the current amount of buffered stdin data.
6116 static int ssh_sendbuffer(void *handle
)
6118 Ssh ssh
= (Ssh
) handle
;
6121 if (ssh
== NULL
|| ssh
->s
== NULL
|| ssh
->protocol
== NULL
)
6125 * If the SSH socket itself has backed up, add the total backup
6126 * size on that to any individual buffer on the stdin channel.
6129 if (ssh
->throttled_all
)
6130 override_value
= ssh
->overall_bufsize
;
6132 if (ssh
->version
== 1) {
6133 return override_value
;
6134 } else if (ssh
->version
== 2) {
6135 if (!ssh
->mainchan
|| ssh
->mainchan
->closes
> 0)
6136 return override_value
;
6138 return (override_value
+
6139 bufchain_size(&ssh
->mainchan
->v
.v2
.outbuffer
));
6146 * Called to set the size of the window from SSH's POV.
6148 static void ssh_size(void *handle
, int width
, int height
)
6150 Ssh ssh
= (Ssh
) handle
;
6152 ssh
->term_width
= width
;
6153 ssh
->term_height
= height
;
6155 switch (ssh
->state
) {
6156 case SSH_STATE_BEFORE_SIZE
:
6157 case SSH_STATE_PREPACKET
:
6158 case SSH_STATE_CLOSED
:
6159 break; /* do nothing */
6160 case SSH_STATE_INTERMED
:
6161 ssh
->size_needed
= TRUE
; /* buffer for later */
6163 case SSH_STATE_SESSION
:
6164 if (!ssh
->cfg
.nopty
) {
6165 if (ssh
->version
== 1) {
6166 send_packet(ssh
, SSH1_CMSG_WINDOW_SIZE
,
6167 PKT_INT
, ssh
->term_height
,
6168 PKT_INT
, ssh
->term_width
,
6169 PKT_INT
, 0, PKT_INT
, 0, PKT_END
);
6171 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_REQUEST
);
6172 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
6173 ssh2_pkt_addstring(ssh
, "window-change");
6174 ssh2_pkt_addbool(ssh
, 0);
6175 ssh2_pkt_adduint32(ssh
, ssh
->term_width
);
6176 ssh2_pkt_adduint32(ssh
, ssh
->term_height
);
6177 ssh2_pkt_adduint32(ssh
, 0);
6178 ssh2_pkt_adduint32(ssh
, 0);
6187 * Send Telnet special codes. TS_EOF is useful for `plink', so you
6188 * can send an EOF and collect resulting output (e.g. `plink
6191 static void ssh_special(void *handle
, Telnet_Special code
)
6193 Ssh ssh
= (Ssh
) handle
;
6195 if (code
== TS_EOF
) {
6196 if (ssh
->state
!= SSH_STATE_SESSION
) {
6198 * Buffer the EOF in case we are pre-SESSION, so we can
6199 * send it as soon as we reach SESSION.
6202 ssh
->eof_needed
= TRUE
;
6205 if (ssh
->version
== 1) {
6206 send_packet(ssh
, SSH1_CMSG_EOF
, PKT_END
);
6208 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_EOF
);
6209 ssh2_pkt_adduint32(ssh
, ssh
->mainchan
->remoteid
);
6212 logevent("Sent EOF message");
6213 } else if (code
== TS_PING
) {
6214 if (ssh
->state
== SSH_STATE_CLOSED
6215 || ssh
->state
== SSH_STATE_PREPACKET
) return;
6216 if (ssh
->version
== 1) {
6217 if (!(ssh
->remote_bugs
& BUG_CHOKES_ON_SSH1_IGNORE
))
6218 send_packet(ssh
, SSH1_MSG_IGNORE
, PKT_STR
, "", PKT_END
);
6220 ssh2_pkt_init(ssh
, SSH2_MSG_IGNORE
);
6221 ssh2_pkt_addstring_start(ssh
);
6229 void *new_sock_channel(void *handle
, Socket s
)
6231 Ssh ssh
= (Ssh
) handle
;
6232 struct ssh_channel
*c
;
6233 c
= smalloc(sizeof(struct ssh_channel
));
6237 c
->remoteid
= -1; /* to be set when open confirmed */
6238 c
->localid
= alloc_channel_id(ssh
);
6240 c
->type
= CHAN_SOCKDATA_DORMANT
;/* identify channel type */
6242 bufchain_init(&c
->v
.v2
.outbuffer
);
6243 add234(ssh
->channels
, c
);
6249 * This is called when stdout/stderr (the entity to which
6250 * from_backend sends data) manages to clear some backlog.
6252 static void ssh_unthrottle(void *handle
, int bufsize
)
6254 Ssh ssh
= (Ssh
) handle
;
6255 if (ssh
->version
== 1) {
6256 if (ssh
->v1_stdout_throttling
&& bufsize
< SSH1_BUFFER_LIMIT
) {
6257 ssh
->v1_stdout_throttling
= 0;
6258 ssh1_throttle(ssh
, -1);
6261 if (ssh
->mainchan
&& ssh
->mainchan
->closes
== 0)
6262 ssh2_set_window(ssh
->mainchan
, OUR_V2_WINSIZE
- bufsize
);
6266 void ssh_send_port_open(void *channel
, char *hostname
, int port
, char *org
)
6268 struct ssh_channel
*c
= (struct ssh_channel
*)channel
;
6271 logeventf(ssh
, "Opening forwarded connection to %s:%d", hostname
, port
);
6273 if (ssh
->version
== 1) {
6274 send_packet(ssh
, SSH1_MSG_PORT_OPEN
,
6275 PKT_INT
, c
->localid
,
6278 //PKT_STR, <org:orgport>,
6281 ssh2_pkt_init(ssh
, SSH2_MSG_CHANNEL_OPEN
);
6282 ssh2_pkt_addstring(ssh
, "direct-tcpip");
6283 ssh2_pkt_adduint32(ssh
, c
->localid
);
6284 c
->v
.v2
.locwindow
= OUR_V2_WINSIZE
;
6285 ssh2_pkt_adduint32(ssh
, c
->v
.v2
.locwindow
);/* our window size */
6286 ssh2_pkt_adduint32(ssh
, 0x4000UL
); /* our max pkt size */
6287 ssh2_pkt_addstring(ssh
, hostname
);
6288 ssh2_pkt_adduint32(ssh
, port
);
6290 * We make up values for the originator data; partly it's
6291 * too much hassle to keep track, and partly I'm not
6292 * convinced the server should be told details like that
6293 * about my local network configuration.
6295 ssh2_pkt_addstring(ssh
, "client-side-connection");
6296 ssh2_pkt_adduint32(ssh
, 0);
6302 static Socket
ssh_socket(void *handle
)
6304 Ssh ssh
= (Ssh
) handle
;
6308 static int ssh_sendok(void *handle
)
6310 Ssh ssh
= (Ssh
) handle
;
6311 return ssh
->send_ok
;
6314 static int ssh_ldisc(void *handle
, int option
)
6316 Ssh ssh
= (Ssh
) handle
;
6317 if (option
== LD_ECHO
)
6318 return ssh
->echoing
;
6319 if (option
== LD_EDIT
)
6320 return ssh
->editing
;
6324 static void ssh_provide_ldisc(void *handle
, void *ldisc
)
6326 Ssh ssh
= (Ssh
) handle
;
6330 static void ssh_provide_logctx(void *handle
, void *logctx
)
6332 Ssh ssh
= (Ssh
) handle
;
6333 ssh
->logctx
= logctx
;
6336 static int ssh_return_exitcode(void *handle
)
6338 Ssh ssh
= (Ssh
) handle
;
6339 return ssh
->exitcode
;
6343 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
6344 * that fails. This variable is the means by which scp.c can reach
6345 * into the SSH code and find out which one it got.
6347 extern int ssh_fallback_cmd(void *handle
)
6349 Ssh ssh
= (Ssh
) handle
;
6350 return ssh
->fallback_cmd
;
6353 Backend ssh_backend
= {
6362 ssh_return_exitcode
,